> Honestly, try browsing the web for a few minutes and it gets uncomfortably hot.

I really haven't had that experience in quite a while. I am mostly running DanctNIX or postmarketOS 22.06 with Phosh and browse with Firefox (with uBlock Origin - I also have a second Firefox profile that has NoScript installed for sites that just have too much janky JavaScript) or Epiphany.

It may help that the south of Germany is not super hot (just hot) and that I use Biktorgj's Modem firmware.

Edit, example: I am writing this in Firefox on postmarketOS while having 4 other tabs open and also two more apps (Tootle and Secrets), and the phone isn't even slightly warm.