Most people are on a CGNAT these days, drowning in captchas is the new normal. You’re at the mercy of one of your neighbors not hosting a botnet from their home computer.
Not even remotely true, I genuinely have no idea what you're talking about. The only time I get captcha'ed is when I sometimes VPN around, or do some custom browser stuff and etc. I'll even say I get captcha'ed less now than maybe 5 years ago.
For better or for worse, CF's fingerprinting and traffic filtering is a lot more in-depth than just IP trend analysis. Kind of by necessity, exactly because of what you mention. So I'd think that's not as big a worry per se.