Pixel A's are quite affordable. GrapheneOS is open source so if there was a need, people could get it to run on insecure devices that aren't Pixels. Expecting that to be done by GrapheneOS developers who care about security just seems weird.

> Pixel A's are quite affordable

There's first-world, upper-middle-class affordable (~$500) and then there's global affordable (<$250).

I got a Pixel 7 secondhand (but good condition) for the equivalent of about $270. It would have been less but I needed 256 gb of storage.