I am nearly in disbelief how persistent this awful pattern has been and will continue to be for a while yet. Always a chance that once it changes to something good that could lock for a long time as well. Things always even out. This is really frustrating though.
In your user dropdown menu in the top right corner, there is an "Ignored Users" tab. In that page you can add users to the list to ignore their posts.
I'm guessing you went to their page directly. Common sense on most sites, but not here