I was hoping people would say, oh this is just the way of martial arts teaching, he just wants you to do well etc
Um. Well. It can crop up occasionally, as a teaching method, usually in the very traditionally-minded clubs. But you aren't enjoying it, so who cares? I hate the "I will criticise you lots, because you are so talented and could do so much better, and just be nice to those other ones who are crap and will never progress but I want them to give me money" bullshit. A decent teacher wants everyone in their class to improve to the best of their ability.
Could you complain about him to a regulatory body - try to get another instructor for the class?
Possibly, but a lot of martial arts clubs/organisations don't work like this. It's usually the case that the club is a small business, owned and run by the chief instructor, which does a certain amount of paperwork/compliance to affiliate itself to a larger organisation (amount of effort required for affiliation varies enormously). Generally, if you complain to the regulatory body, one of three things would happen:
- they pass your complaint to the police, e. g. if it was safeguarding
- they strip your club of their affiliation, if it was serious but not criminal
- pretty much nothing, possibly feed the content of the complaint back to the club owner.
OP's instructor doesn't sound like someone I would want to pay money to, but at the same time what is described sounds as much like a personality clash as anything else. Some people really like getting a good shouting at, and it sounds like the club has a fair few happy members.