You didn't mention how many jobs you've had. If you've been at the same company for 9 years, you've likely just built up a ton of institutional knowledge and may not be a "10x developer" in the broader world. As others mentioned, you should probably find a place with better developers than you (I don't know what you're working on, but if you're not like, writing a programming language or a self-driving car or something it shouldn't be too challenging).

> 80% of the code base is my code

It's a bit of red flag imo that you don't seem to consider that being the author of a system naturally makes you much more productive in it, while others have to adapt to your code (essentially, you may be doing a poor job with knowledge transfer). An old CTO used to have a saying "the easiest way to be a 10x engineer is to make 5 other engineers 2x more productive".