I followed this controversy as well. On the GrapheneOS forum, strcat announced he has stepped down to work on himself. The project is running like normal and development is still the same as always.
Fairphone is also guaranteed only 5 years. If not, then they are probably using a custom ROM that is not directly supported by Google. I’ll keep my eye out for this company though, the repairability is great and I love the repairability of the phone.