Example (spam post containing an amazon affiliate link, post hopefully deleted by now but I assume mods/admins can see it): https://lemmy.world/post/15846936
Also there are tons of links people post legitimately but have tracking parameters, gclid=this, fbclid=that, etc. Those can be cleaned up too.
By editing out these parameters automatically when the link is posted, people’s privacy can be protected and the incentive to post affiliate spam can be decreased.
It could be a server config parameter and/or put into the posting UI: “your post contains [link] with flagged parameters, choose between a) post cleaned up version (shown), or b) post link without changes (may go into moderation queue depending on community settings).”
I mean the lists for this already exist because there are firefox plugins that do this and often these kinds are open source. This could surely be a case for crowdsourced / collaborative data.