I mean, you literally are not even mentioning the option that has exactly what you want defined as it's core values.
Whenever I hear all this lamenting about Apple this, Microsoft that, Google rablerablerable ... we have been told about all of this sine at least 1989! I'm full-time, work and private, on a Free desktop OS since 10 years +. Just put your money and effort into the Free alternative.
I have a rooted and custom rom android phone running an official lineage os release
It still can't make phone calls without cycling airplane mode between calls.
The one before that would crash if I paired a bluetooth device while connected to one already.
Both of them bootloop at the power off battery charge screen, which basically means i couldn't turn my phone on while plugged in, and unless its a fast charger, the act of repeatedly booting up keeping the phone screen on ends up draining power faster then it can charge.
So. Tell me again about these free and open options.
Not my experience with LineageOS. My biggest problems with my phone with LineageOS is that I cannot use a microSD card as more internal disk space, not a problem with LineageOS itself, but a problem with Android 6 and above on my phone. The other problem is LineageOS not having an update for my phone for 2 or 3 years, as mine is an old budget phone from 2014.
On the whole I have been very happy with LineageOS as it has allowed me to continue to use my phone for years longer than I would have with the simply bad manufacturer updates that almost completely filled the internal disk space and stopped updating something like 2015 with Android 5. Less unnecessary expense, less eWaste, thumbs up.
For me, I would definitely go with a phone manufacturer that supports rooting their device and put LineageOS on it if I think I need it. I may not install it, but the option for the future is the main thing.
Whenever I hear all this lamenting about Apple this, Microsoft that, Google rablerablerable ... we have been told about all of this sine at least 1989! I'm full-time, work and private, on a Free desktop OS since 10 years +. Just put your money and effort into the Free alternative.