I spent a long time working alongside quants in the City, in several large and small companies. Some of the quants seemed to enjoy their work a lot, a few less so. It depends on the team and the company to a large extent I suspect.

If you really can't find any fun place in the City as a quant, consider eg a data scientist role elsewhere.

I don't think that I have yet paid myself (eg a CTO of start-ups, with an MSc) what you probably got as your opening salary. I worked in IT, but the money wasn't a motivator and so I never moved to trading as friends did, or into management...