I seem to be able to reply and those replies to seem to show up on the server:
https://mastodon.sdf.org/@ShaunMusgrave/110641423725971570
It is possible they blocked you specifically from the server and at the server level rather than the whole of QOTO.
As you know your tendency to tell people you blocked them has agitated many people and generated a lot of reports for you. This may have led some server admins to black list you and block your account from their server. It is even possible you have been added to a shared block list, though thats not super common.
That said I am only speculating, it may be something else entierly.