Some of those people will also buy a premium phone because they want to have a great camera system.
Absolutely. Vanilla Android is actually very nice, and compatible with many types of devices (phones, tablets, TV boxes, now some laptops). In fact, I recently compiled and patched an x86_64 version of LineageOS for an HTPC and it blows ordinary Linux distros out of the water in that role. Fully usable with remote only, etc. The problem with Android is that commercial versions people are used to are riddled with Google spyware and OEM crapware.
Technically you don't even deserve a note of why I am personally interested in a Signature 27, but: GrapheneOS of course, on a top tier design, audio, battery life, display and performance, because I enjoy excelence. Thank me later for shifting your argument from "its for criminals" to "its for corporate ball lickers", now proceed into making a fool of yourself like so.
This is a phone for hackers and drug dealers and enemies of the state and perhaps some types of bankers, and the tinfoil hat Gribble contingent. Everyone in that list will pay whatever it costs without much of a second thought.