The "Enable realtime" feature works very inconsistently, basically it only works well when only one person is typing. If there's another person typing at the same time, a third party will pretty much always see garbage in there, basically letters of two posts interleaved into one. I think it even happens sometimes when only one person is typing and the connection is spotty.
It also has trouble with removing the posts after they get posted, this can also add to the confusion with the bugged posts because they can get even more mangled. That thankfully gets resolved if you reset your connection to the feature.
Here's a quick mockup, top left and top right are the pov of the 2 users typing, bottom is what the 3rd user sees. It gets way more unreadable when there's typing going on on 2 ends of course but this demonstrates the situation well enough.