As a linux user you should know that all VPN companies are as trustworthy as a chronic liar, and therefore not rely on one. So it doesn’t matter that they don’t support Arch, really. And even good that they don’t support Tails.

Isn’t VPN a must-have to avoid IP-tracking without downsides of Tor (slow, Cloudfare etc.)?

You’re only shifting the tracking from your ISP and the target server to the VPN company, which is just as likely to talk.

No, I mean, if I want a website to not know who I am? Isn’t Brave or Librewolf with fingerprinting protection and a VPN a valid choice?

Would prefer a random non transparent proxy for that. Or just only use IPv6, and have your router rotate that every so often. And, of course, minimize traffic to bad websites.