I never bought any ebooks off Amazon without removing the drm at the time. I did buy a lot of shows and movies, but if they take those away, I'll just pirate them, given I've already paid.
Unfortunately not everything is available on the high seas. For instance, it's impossible to find older seasons of MasterChef Australia (in HD). Heck even trying to view it legally, outside of AU, is a mission - Amazon is the only entity that has the older seasons. I ended up subscribing to a Prime account just for this.
PIA also supports port forwarding from non-US regions. And the Linux solution is better and provides a stable port, unlike Proton's 'run this command every 60 seconds and hope'.
I only use OpenVPN (another reason to move away from Mullvad), not their own clients. I moved away from PIA in the past, I don't remember why, it was a long time ago.
I was happy with Mullvad for a long time, especially being able to buy their scratch cards, but now I had to move to Proton due to the deprecation of port forwarding and openvpn at mullvad.
But PIA is american anyway so that won't work for me, I'm not signing up with new american services anymore since Trump came to power again.