I've been extremely fortunate and that most of my recent managers have been okay with me either completely rewriting the code base, or implementing my own practices. I have no qualms about leaving a job where I'm not able to do my best work.
Any experienced developer is going to dislike her new team's code. It's just the way developers are. They like the code to match the way they think or what they're used to. New code bases are always counter-intuitive at first, and it feels like that wastes your time.
That means every new, experienced hire is going to want to refactor. It does not mean they should refactor or that anything is actually urgently wrong with the code.
I've had people who refactored, broke their build, couldn't fix, and ended up scrapping the branch entirely. It was a complete waste of time.