I get what you're saying as far as realistic time frames for events and showing the passage of time. However this an endemic problem in all television shows. All of them, regardless of their other attributes and whether they're episodic or serialized, are in the "adventure of the week" format. If we think about it, almost all of the characters on TV live unbelievably eventful lives that no real person could ever live (even within the parameters of the fictional universe). The audience rarely notices unless this gets too out of hand and starts to erode the suspension of disbelief. As for major changes in the cast, this is being done more often today. "The Walking Dead" is an example where main characters are killed off and others leave the frame of the narrative and then return later. However there are limits, most people (not me necessarily) need at least a few core characters to hang onto.
Problem with that is existing fans are a form of free advertising. Their advocacy face to face, and in social media will bring in people (at least initially) to a new show in a way that print ads, commercials on TV and places like YouTube won't. Catering to a reasonable degree to aging fans like myself (mid-twenties) can only be a plus, and that catering would largely go un-noticed by people seeing the franchise for the first time. Much of exist continuity can be basically pushed into the background, but at the same time neither disrespected, nor eliminated.
I'm amazed at the inordinate amount of time some fans spend trying to convince all and sundry (perhaps themselves most of all) that fandom doesn't matter and paying attention to anything it wants would be death. I mean, it's true that creators need to pursue their own vision with integrity and that crude fan-pandering is invariably lame... but in this day and age, when geek is mainstream and honest-to-God "normal people" attend conventions and do cosplay and stuff, it still feels like some people are cringing under the lash of Shatner's long-ago "Get a Life" sketch. It's a sad thing to see.
You're right, the people in charge of franchises have to consider the core fan base. They are sort of a center that a larger audience can be built around. You have to give them a product they will be satisfied with but also strive to reach new people who aren't familiar with the material. That's the line the JJ movies tried to walk (with varying degrees of success). We will never see a direct continuation of Berman era Star Trek but a new series won't completely throw everything out either.
This discussion parallels another currently running in the TOS forum. Namely what core elements might, could or should be carried over into a reboot, particularly an extensive one?
I can handle a minor reboot, or a 'preboot' as I like to call it. Go back to the beginning with the TOS characters. Keep the basic aspects of the characters the same, but allow the writers and producers to explore new territory with these characters that otherwise wouldn't fit with canon. Obviously, make it as visually stunning as you can (though I don't need great effects to enjoy a story.) I can't handle a complete reboot where everything is changed just for the sake of being different. I'd get angry and kick the dog.
I really don't want to see another reboot. I'd rather them do something with the one they have now or the prime universe than to clutter up the multiverse with another reboot that might not even stick.
Ha, I guess we should all believe in magic unicorns as well. The only thing important to TPTB is ST's name recognition, hence Abrams using a bunch of familiar names and concepts and creating his own version of Trek that is nothing like TOS. Any new Trek will be a copy of whatever is popular with the name Star Trek slapped on it.
I mean, obviously they don't "have to" consider anything, there's many a Trek movie as testifies to that. But that doesn't equate to fandom being irrelevant and considering its wishes as being market death.
Fans don't know what they want or more honestly they want their own private fantasy world with the characters from the franchises they like. What most will respond to is good stories and interesting characters. The Marvel movie franchise is proof of this. The ugly truth is that you can always create new fans. Look at Star Wars or Doctor Who.
Yes and no. Can you "always" create a fan base forty million strong whose devotion drives a multi-billion dollar franchise and is willing to come out and see your movie multiple times if you put the slightest effort into it? Not exactly. If Paramount could do this at the drop of a hat you can bet they would have done it many times over. Of course, the lovely thing about such a fan base is that it will stick around through enormous amounts of abuse, so in that sense "ignore the fans" can seem like good advice in the short term.