It is not the job of GrapheneOS to lower their standards and deplete their resources supporting every phone under the sun. We already have LineageOS for that. I would rather not be snarky but I don't understand why people keep blaming GrapheneOS instead of the OEMs. Almost every single time.
I don't think that there is anyone to blame.
GrapheneOS has requirements that result in only the Pixels being supported. LineageOS has other requirements that result in most phones being supported.
I may wish that more devices met the requirements of GrapheneOS, because I like GrapheneOS and their requirements, but I find it very weird to with GrapheneOS changed their core vision. What makes GrapheneOS is those requirements.