Reduced security has always annoyed me a bit as an argument.

Security is one of one of the main selling points of GrapheneOS, I can fully understand that they don't want to weaken that by supporting fundamentally insecure devices.

I think a nice side-effect is that they only focus on a small number of devices (Pixels) and support those really well. I have followed the /e/OS forums for a while and many devices have constant regressions because it is hard to validate each release on tens of devices.

I get all or nothing when your threat model is state actors.

People do have different thread models, though I think up-to-date software should be the baseline for everyone and where pretty much every phone outside iPhone, Google Pixel, and a subset of Samsung phones fail. Also, I think having a secure enclave should be the baseline, since phones do get stolen.

Its also an easier sell to people who are apathetic to security when the product is just better and more secure, the same way apple does

That's really a weird example though for supporting the argument that GrapheneOS should support more devices. Isn't Pixel + GrapheneOS then pretty much iPhone + iOS? Privacy-respecting, secure, not pushing AI subscriptions all the time (though iOS is getting worse in that respect), offering useful functionality?

At any rate, I understand if you have another phone, you wouldn't buy a Pixel for GrapheneOS, but it does make sense to buy your next phone for running GrapheneOS. Pixel covers a pretty wide price range to, e.g. the Pixel 9a was 349 Euro here recently, all the way up to the Pixel fold.