There are already tools for that, and it will probably get easier with time. In general, people should be encouraged to create multiple accounts on different servers from the beginning, so they already have built in options if they want to leave.

I use different sorting algorithms on my different accounts and also have different subscriptions, so the front page often looks totally different when I sign into my alts. Some of them are even federated with hexbear 🫣. I always find interesting posts that I missed by doing that.