Personally I (almost) no longer agree to terms and conditions, because I ~fully migrated to open source software 
In those links, Novacustom sell already prepared computers, these computers work well and are widely compatible. There are also more sellers. If you have not heared about NovaCustom, here Techlore recently made a video how much NovaCustom care about privacy Finally! True Privacy in a Laptop: NovaCustom Review - Techlore.TV - Digital Rights For All
But one cannot do this oneself on random hardware, because its very difficult (it costs ~tens of thousands for them to prepare a computer line with coreboot).
Its debatable if that is the case, but depends on your specific situation. But my quality is not reduced (but improved) by using all alternative private software and services. Maybe explore case by case, what you could further upgrade to private alternatives. Maybe it would not be as bad as you may predict.
Find you way which would be less exhausting. For busy people, I am personally recommending https://privacyacademy.com/ which is a polished course for non-tech people (but JG wrote a different opinion than mine here: The digital euro has enraged half of Brussels (but there is great alternative path) - #11 by JG )
I still don’t think that privacy is connected to being rich. For example, here grassroots activists (in Russia etc.) created an encrypted messenger for themselves, so ‘code’ will still be available and encryption will still work to anyone who will care to use it FOSDEM 2025 - Delta Chat, from e-mail messaging to Peer-to-Peer realtime networking