GrapheneOS + Obtanium/F-Droid feels pretty unruggable to me. I suppose Google could do something to brick Pixels but not without seriously hurting themselves. Seems like the best solution atm.
Discussion
I think your right about it being the best solution for now. Lineage rom seems a fairly good option too for those who still need some basic google services, and it's available on way more hardware.
Really though we need a fully FOSS phone, open source software, open source hardware. Go FOSS or go home 😅