Daystrom Institute

The Syrrannites being called a "violent cult" was propaganda by a corrupt regime trying to rewrite Vulcan history to keep themselves in power. They were deliberately suppressing beliefs and practices related to the Vulcan telepathic nature, because this posed a threat to them.

Vulcans, valuing rationality as they do, reacted differently than humans would to the exposure of the misconceptions and outright lies that had been propagated by Vulcan high command. Most of society reevaluated their beliefs and taboos around telepathy and the more spiritual nature of being Vulcan. By the time of TOS, Vulcan society had mostly reconnected with their more spiritual and pacifistic traditions and abandoned the more modern, arrogant and hypocritical views espoused by the High Command of the Enterprise era.

This tells an interesting story actually, of how humans and Vulcans (and Andorians) benefited on a societal level and became better people together through the cultural interactions and exchanges that took place during that era. Prior to Enterprise, we kind of knew that humans had benefited technologically and culturally through their contact with Vulcans. Enterprise showed us how Vulcans benefited and rediscovered themselves (and went through major and positive cultural revival) as a result of their contact with humans. I think it's kind of a beautiful story.

Yes, we see TPol reading the new rediscovered teachings of Surak, demonstrating the spread in new ideas

We also see the Vulcan ambassador standup for being a “deviant” and ultimately prevail, demonstrating a shift in attitudes.

The Vulcan arc was one of the most strangely satisfying because:

• It begins strong in the first 5 episodes or so (until Trip gives Tpol pecan pie)
• Goes into the back burner for 2.5 seasons, except for random jabs at the Vulcan High Command
• Goes into overdrive in S4 and shows us how these Vulcans become the ones we’ve come to know.

I think one thing to add here is that spock was considered somewhat of an outsider with his half human hereditary. It's likely his use of the practice was part of his wider view of things. Also the reputation of mind melds may have improved via spocks reports and his strong character.

I'd argue to some degree, but at least in TOS, the only contact we have with Vulcan culture is through Spock, who isn't that traditional a Vulcan.

At the very least, he mind melds a lot more than Vulcan cultural tradition would suggest, with all kinds of beings that aren't other Vulcans. It is entirely plausible that Spock is simply more liberal when it comes to mind-melds than other Vulcans.

Enterprise might well have gone the other way, where T'Pol represented a more conservative faction of Vulcan society, that prefered to avoid mind-melds due to the risk.