Yeah, if you keep your leetcode skills sharp and study to game the "design" interviews, you can get a job at a competing company instead of playing the depressing political game. As a bonus you'll make significantly more than internal promos.
All said, I likewise would find it difficult as OP to work at a large company where local incentives can be so misaligned to the company's. Hence, the advantage of working at start-ups.
I found practice interviews on interviewing.io very useful