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.