Yes, if Signal has effectively removed ratcheting and forward secrecy from the logical "encryption protocol" by encrypting all messages (even disappearing messages) with a single static key that never changes for your lifetime and sending them to the cloud, then all this talk about "post-quantum ratchets" is theater. There are no ratchets.

I think it's a valid point but also that it assumes a lot about the threat model that can be disputed, so your "theater" point is not well taken.