Why are people with a CS degree so rejecting to career changer

Many aren't. For many it's just a job and they'd happily take a job in another field with better pay and benefits. But that's not super common right now. For the last 20 years dev jobs have been some of the cushiest available.

If its more than 'just a job', there aren't lots of options that are similar. You get problem solving, system design, and working in a mostly abstract space. You can find other careers with 2 of those things fairly easily, but all 3 is somewhat unique. And when you find all 3, the pay and benefits aren't comparable (pure math careers come to mind).

What other careers would you suggest?

I really like being indoors with a comfy chair and a/c and not having to talk to humans. Seems to me that any career change would take me out if this comfort zone.

I don't even want C level jobs because fuck meetings.

Are they, though? I mean, are they any more so than anyone else? I personally know a handful of talented devs who have pivoted out of the industry entirely.