PatchLake I’m curious, is there a reality where no future Pixels can be supported?
That's up to Google... or, if Google is forced to sell Android, to the future owner of Android... or perhaps to government regulators in various countries... "It is difficult to make predictions, especially about the future."
Personally, I suspect the picture will be somewhat clearer when the Pixel 10 is released, and then clearer again when Android 17 comes out. Meanwhile it is likely that there will be various speculation, some of which will eventually turn out to have been more accurate than the rest.
Please note that I do not speak for the GrapheneOS project.