Two posts, two different instances, two different sets of comments. Ok, there are pros and cons:
Segmenting the conversation means that different opinions and perspectives have a bigger opportunity to rise to the top in each discussion. That’s good.
There is also a risk of too few different viewpoints being present in one instance or another, making the possibility of an echo chamber forming higher. That’s bad.
I’m not suggesting that there’s a single perfect way to handle it, nothing is that black and white, but maybe there is a chance to do better. Perhaps crossposted content could contain a second link underneath between the body of the post and the comments section that could inform users that an identical post existed on another instance. Perhaps the comment sections could be merged but the user could choose to filter by instance if they wanted to.
Maybe if the cross post could be identified and the comments merged into tabs where you can jump between them for the same post. So instead of 5 copies of the same link showing up with 5 sets of comments all of them are merged to one and when you click on the comment section it allows you to cycle through all of the different instances discussing it. It would clean up the feed but still allow you to see what each group is saying and where they are saying it.
I’d love to have a link for a news article wheee I can jump between what all the various instances are saying so I don’t miss anything.