One thing I have learned from being gender critical is to "unbundle" these packages of political positions broadly sold as "left" or "right".
Back in 2016 I voted Remain and like you, I was rather disdainful of those who voted Leave.
However, when the "left" left me over sex realism, I took the opportunity to re-examine my other beliefs too.
So no, this isn't the only benefit of Brexit. As with most things, there are various pros and cons. Scratch the surface harder and you'll find plenty of ways in which the EU packages political positions together that should be unbundled.