Constantly reposing duplicates en-mass makes the experience way worse for those of us who don't have a personal vendetta against particular target lemmy instances and who haven't defederated with them out of spite or distaste

It's not possible to cater things in a way that's pleasant for everyone at once. Your slightly degraded experience, is another's "godsend" be it because they were forced out of .ml because of the "horrible" crime of supporting ukraine or calling out Russian propaganda or because by choice ala instance defederation or choosing to block them

Hence the reason people say, you need to cater your feed for an optimal experience.