This now begs the question for me as a user: Which one do I subscribe to if I want to stay informed? An article on one side could be submitted or gain traction when it does not on the other. But subbing to both could lead to a lot of duplicate articles being fed to me.

Theres nothing stopping the client from offering a different or entirely customizable view to the content.

For example the client could allow user to place those communities under a common News category in their client. Then the client would combine all identical links in the category according to some criteria (e.g same link posted in the same day would count as identical) and either merge the comments or let the user pick which communitys comments to see, or preferably both. So comments section could have a buttons for "Comments at news@beehaw.org", "Combine comments" etc.

I think it should be possible to build a client that hides most of the details about different instances and such so it would function almost the same as traditional RSS readers.