I made a free macOS App Store app that unlocks higher brightness (actually higher nits, not just a color filter). It works by forcing HDR content. I've only tested it on my MacBook Pro 14" M5, but I assume it works on most modern macbooks.
The description says "The best screen poster", but it's meant to say "The best screen booster" (overly aggressive autocorrect in macOS probably).
Yeah that's maybe too hot actually. But it actually matters which colour/finish your Mac is. The black one gets significantly hotter than the silver in the sun. I sometimes "hang" my shirt behind/on the top edge so that it blocks the sunlight, that also cools it down quite a lot. Enjoy though:)