The point is to flex their power while still maintaining a veneer of deniability. Everyone knows what's going on, but their supporters will still use it as a pretext to argue that nothing is wrong.

It's the same reason Israel claims that every building they level in Gaza is a military target.

It's the same reason cops in the US cite noncompliance as a justification for violence.

It's the same reason Republicans allege voter fraud when they make laws to suppress millions of votes.

Authoritarians will never, ever, ever admit "we're dictators" or "this is about power". They will always have an excuse for it.