The constant pervasive ideas about the Jedi, that they're repressed and bad at relationships and isolated from the world and its realities and stuck in their ways, is actually just... Anakin.

Like people looked at Anakin Skywalker and assumed that because he was the protagonist that the way he acted was somehow a symptom of the Jedi's teachings or upbringing instead of just... Anakin's personality?

Anakin is repressed, more than almost literally any other character in the entire franchise. Anakin chronically refuses to really acknowledge how he's feeling and pretends he ISN'T feeling it while multiple other people might be begging him to do the opposite.

Anakin is bad at relationships, he pressures Padme into a relationship by constantly ignoring her stated boundaries and disrespecting her. He complains about his OTHER relationships to Padme and Palpatine, particularly his relationship to Obi-Wan. He's awkward and overly melodramatic, incapable of truly expressing himself in a way that isn't immediately off-putting to normal people or being able to express his more positive feelings towards someone in a way they might recognize or accept.

Anakin isolates himself from the world and its realities, refusing to see nuance anywhere, and preferring to view things from an entirely black and white perspective, particularly in order to make himself out to be the hero of any situation (the Tuskens are animals, the Separatists are evil, the Jedi are evil, etc).

Anakin is stuck in his ways. Similar to the last point, Anakin refuses to accept that any way but his own could possibly work or be worth considering. He thinks he's extra special and therefore people like Obi-Wan have literally nothing to teach him of any worth. Anakin doesn't WANT to think differently about the Separatists even when Padme tells him otherwise. Anakin does things in a certain specific way and refuses to change even if it might be better to do so.

I dare someone to try to come up with an accusation made about the Jedi's culture and lifestyle that "needs to change" that isn't literally just ANAKIN'S personality flaws projected onto the Jedi at large.

Maybe the Jedi don't need to change at all and Anakin just as an unhealthy toxic personality that even the Jedi couldn't fix.