The core criticism to the vendor is the missing security element. This is a fair point.
However, calling out on e/OS in the same post, seems to me very counter-productive. We need more OS vendors and less infighting. Calling all custom ROMs insecure and claiming to be the only one is IMHO 'drama'. Particular there are contributions of me microG that are helpful if you want to de-Google ones phone. Graphene has a different approach: fair. People will use GrapheneOS if they share their goals.
Fairphone is about sustainability and a bit about not supporting major tech like Google. I don't think this hurts. In an ideal world we could have both. But sustainability seems to be a non-goal of GrapheneOS.
I think in this context it's fair to call out /e/.
In some ways /e/ and GOS are trying to achieve different things (/e/ is not hardened and does not claim to be), but /e/ is severely lacking security wise compared to AOSP.
This [0] is, in my opinion, a fair review that mentions many of the issues. That Fairphone is ok with these is telling about their position on privacy and security.
[0] https://www.kuketz-blog.de/e-datenschutzfreundlich-bedeutet-...