Crawl Budget Issue: 900K Redirected URLs Slowing Googlebot?

I'm managing a website with 500K indexed URLs and 1.5M pages with redirects (according to GSC). I’m seeing that 7% of Googlebot's activity is spent on 301s, and 900K of those are redirects from old non-HTTPS and AMP URLs (set up in 2021):

• http://example.com → https://example.com
• http://amp.example.com → https://example.com

The problem is, I'm noticing a decline in impressions over time, but my Average Position remains unchanged, leading to fewer clicks. I suspect Googlebot is spending too much time crawling these old redirects instead of my new content. Also, I have 200K URLs with two chains of 301 redirects that I haven't been able to simplify.

Here are my questions:

• Should I be worried that Googlebot is wasting valuable crawl resources on these old redirects? Could this be affecting my impressions?
• Why is Googlebot still crawling these old non-HTTPS and AMP URLs after 3 years of 301 redirects?
• Are the two-hop 301 redirects something I should prioritize fixing?
• Would it make sense to start removing old AMP and non-HTTPS redirects using 410 (Gone), and just keep the ones that have backlinks (based on Ahrefs)?