Please correct me if I'm wrong. Secdroid was in the beginning an app used by the French ANSSI to harden their custom Android operating system. It was running on some public insecure devices like the Xperia or Crosscall.
The used in the past the secdroid app created by an XDA member to harden the kernel and other things but why would they do that now since GrapheneOS is already doing all the hardening job ?
I will not be surprised if some couples of new phones are delivered with a modified version of GrapheneOS to the French government workers. ANSSI is interested by GrapheneOS hardening work.
The FBI used in the past some of the GrapheneOS code for the ANOM phone.