I've often wondered about that. I suspect Vulcan's are way more powerful in telepathy than Betazoids (They can transfer their entire consciousness) yet they don't practice in casual mind reading like Betazoids do, & probably not because they couldn't, but rather because they'd disciplined. It is kind of rude to tramp through people's thoughts like that. Even Q said soShe actually does not use her powers that way because she told her own mother that their ways are rude to others

To be fair, Guinan's friendly advice more over takes the form of sage wisdom from a mysterious creature who has special insights, which Troi just never really seemed to equal, even with her telepathic skillsShe actually acts like a real therapist where Guinan just gives you some basic advice that a friend would give.
This is an often overlooked benefit of the character imho. She is basically a cultural advisor & psych profiler. We can debate the point of having a therapist on the bridge, but there's no doubt a Starfleet trained culture specialist, with a psych background, & who's a semi-telepath as well, is something so valuable that they ought to be as adamant about having them on all bridges as they seem to be about having every ship get an android like Data.She was good at giving feedback about different aliens, though.
It's a fair point. I feel the same way about Geordi getting the all-encompassing character assassination of being permanently labeled a creep, because he handled one crush badly, & is a bit romantically awkward in a couple other encounters.I sometimes think this Guinan thing was embellished by the Troi is useless crowd. I heard it ages ago and now it's being so pushed like a fact and things seem to be being reimagined. Or it just got stuck in people's heads as a fact rather that an opinion or a preference in who you would prefer to talk to.
So, now he's a poster boy for everything wrong with incels or something, whereas Barclay is way worse socially but actually seems to get a pass because he reads more neurodivergent, & so we should feel bad for him more or whatever. Geordi isn't that bad.
Where Troi's problem stands out is not so much about her, but that the writers sucked at writing her. Her psychic skill is so plot contingent that its inconsistency tends to bother viewers, & that shapes an opinion of her on the whole that bleeds into other aspects. We're ultimately a fanbase driven by overanalyzing, & that doesn't bode well for flaws of any kind.
I tend to forgive the psychic stuff a bit, for being weekly conjured sci-fi, but they even struggled with how to write her in as a therapist. (Which is more relevant to real life) One of the most obvious cases of therapy needed on the show is Scotty falling out of time for nearly a century, & she is nowhere to be found, even though he's struggling with it.
I'm thinking she came off upset or mad, mostly because of a war going on, which she knows shouldn't be (why she's even still aboard is pretty whacky IMHO) but her dealings with Tasha seemed off because it's supposed to be jarring to her to know this person she shouldn't know. Overall, I agree she handled the mess badly with her. It's certainly not all on PicardI think Guinan is great and even trustworthy, but I would not really want to talk to her about anything too deep and just stick to friendly advice with her. The gaslighting is so true, lol. And her blunt approach to Tasha. I always wondered why she was so mad.