To be honest the specs of the Fairphone are middling and the device is rather expensive for what you get. The Pixels are a much better value, especially with a series. If you want something truly high end, wait for the Motorola with official GOS support.
Without support of alternative OS Fairphone is basically a landfill. Why would anyone buy this apart from novelty factor.
Supporting an alternative OS wouldn’t change the fate of Fairphone, imo. Most people don’t care to move away from the stock version of Android that comes with their phone or iOS.
This isn't a hypothetical, Fairphone supports alternative OSes. Heck, you can even buy it with /e/OS in their store:
https://www.fairphone.com/the-fairphone-gen-6-plus-e-operati...
tbf that was just more so me insulting fairphone and kinda unnecessary from me
I mean, aside from /e/OS as a first-party option, there are also official Lineage builds[1]. And they're at least a target for PostmarketOS[2], even if that wiki doesn't actually describe something daily-driveable yet.
[1] https://forum.fairphone.com/t/official-lineageos-23-for-the-...
[2] https://wiki.postmarketos.org/wiki/Fairphone_(Gen._6)_(fairp...