Couple of things:
1. Tim Drake is not gay, but bisexual. Currently in a same-sex relationship, but still attracted to girls. So the argument about his feelings for his past girlfriends doesn't apply at all.
2. Though, as a Conan fan, I hold Roy Thomas in high regards, he can be a total dumbass and even asshole at times, as evidenced by his claim of co-creatorship of Wolverine.
3. Retcons of characters and their motivations have been a part of superhero comics pretty much since the beginning, and Thomas himself has done it a lot of the time. So, just because he wrote Alan Scott as a heterosexual character doesn't mean shit.
4. While Dixon was one of the best writers of the 1990s, especially for the "grounded" characters, he has grown into an even bigger dumbass and asshole than even Thomas is capable of in his worst moments.
1. Yeah, I'm aware that Tim was retconned to be bisexual. But that's the thing; prior to that retcon was there ever one single indication that he was attracted to men?
2. I don't doubt what you say about Thomas. I've maybe read a couple of comics from him if that. He seems like he does have a bit of homophobia going on (although in the interview I read, he said he has nothing personal against gays). It's probably largely a generational thing. Speaking for myself, I admit, growing up, although I wouldn't say I was homophobic, I will say I was not overly sensitive and/or insensitive about LGBTQ+ folks. That changed in college when I had some as friends and now. They are our brothers and sisters and sons and daughters and they should be welcomed in society and treated in every way as equals and not shunned or persecuted.
3. Yeah, you're right about retcons. Every single DC reboot like Crisis on Infinite Earths, Zero Hour, Infinite Crisis, Flashpoint, Doomsday Clock, and Death Metal (haven't actually read the last two yet, but I got them all, right?), allows DC's publishers and creators to make some changes and they have. Usually, these changes are to reconcile past events and the like, clean up continuity errors, bring back dead characters, and, yeah, make tweaks to character origins and the like. Superman, Wonderwoman, Hawkman, and some others were obviously rebooted and old continuity and the like cleaned away, but the core of all those characters was pretty much the same. The New 52 Superman that Grant Morrison created was kind of shocking to me at first. It was kind of deviation to what John Byrne did for Superman's post-Crisis origin, where he made Superman more human and more as a refugee escaping a very dark and sterile Krypton. Morrison's Superman was less optimistic and more alienated and much more brash and a social justice warrior, which is actually what the character was initially.
And, of course, James Robinson's reboot of the JSA characters on Earth 2 was far far more drastic than anything done in the Earth Prime DC books. And, again, I felt, due to the nature of that book and the deconstruction or re-interpretation or reboot what have you that was it's vision or mandate, that that was all fine. These were new characters that had the names and some of the elements of the original JSA characters, whose most distinctive characteristic perhaps was that they were all tethered to the time they were created, the pre-War late 30s.
But changing the sexuality of a character is a very extreme retcon imo. The original Golden Age Green Lantern was not an LGBTQ+ character. He was made one because the Earth 2 character was gay and that character was in comic book limbo while the GA GL was coming back. And the only reason the Earth 2 character was gay was because the Obsidian character, the gay son of the GA GL, was put in comic book limbo to begin with. So, really, James Robinson and Dan Didio (twice) were responsible for making the GA GL gay, something he never ever was before.
Also, I didn't think the retcon really followed logically from Doomsday clock anyway when they brought the JSA back from being written out by Dr. Manhattan. Why would re-inserting the formative event and reinserting the missing 10 years alter Alan's sexuality? It's akin to Simon Pegg's lame explanation that the change Nero made in the Abrams ST films went backwards in time to make Sulu gay after George Takei unequivocably said the character he played in the original Star Trek and the films was straight. But, y'know this is par for the course, as you said, for comic books. Sequential logic and especially science (king of drives me crazy as an AE sometimes to see how many writers and artists don't even bother to check some basic things out) are completely secondary to the story and the changes you want to make in a reboot.
4. When you say "grounded" do you mean like the Batman street level characters and the like?
I always thought Dixon was a solid writer and I certainly enjoyed his work on Detective Comics and Robin (I collected a lot of his run there and the start of Nightwing). I don't know much about the man in real life. I've read an interview with him, and, IIRC Denny O'Neil (RIP). Dixon said that while they were on completely opposite sides politically, they respected and liked each other and that he thought O'Neil was a great editor and boss.
I think I heard that he was part of that Comicsgate group. I've always been a moderate dem. I'm married to a Mormon Republican and we have more in common than not as far as our values. And, honestly, as a Catholic neither party maps on with my faith's social teachings, and, for that matter, even I don't subscribe to all my faith's teachings either. There are some things I agreed with in the old Republican party, particularly fiscal responsibility (although that is obviously not a priority anymore with them). So, I don't have a problem with people having a difference in opinion on public policy. I do have an opinion on how we should treat others as people and some of this Comicsgate stuff (and a lot of other more current stuff) I've read about is reprehensible and shameful. Threats, trolling, personal insults, sexism, racism, homophobia, just hatred, blanket statements and condemnation, from one side or the other, that's where I get off. It's wrong and it's incredibly damaging and we're living it right now in this country and were all weaker and poorer because of it.
As far as that Kinsey scale stuff, I've heard about it. My wife is the PhD psychologist so she knows more about it than me, but I'm not really interested or arguing about the plausibility of these changes based on psychology. I know there's supposed to be this sorta scale, but I just don't think it can be used to try to explain in some way, that the original GL AS or even Tim Drake were always LGBTQ+. To me, Alan Scott and Tim Drake were both straight white males based on how they were written and how the ones most responsible for developing them wrote them and I think that should have been honored and respected. Again, that said, I also think that Tim Sheridan's story was certainly worthwhile and legitimate one to tell (and I've read considerable praise about it). I just don't think there's any way to reconcile this depiction of Alan Scott with the pre-Death Metal/Doomsday Clock/Flashpoint version (where exactly did the gay GL AS appear? Did it happen after he returned with the JSA in Doomsday Clock on, or was it after Death Metal?).