I have a lot of scrobbles, and every time I go to the page it has to re-scan my entire list of scrobbles which takes at least 5min. It also makes me not want to share the link with others, if they'll have to sit there waiting for it to load all my scrobbles after I already did that waiting before sending them the link.

It wouldn't solve the link sharing issue, but even just an option to save a client-side cache in IndexedDB so it doesn't take so long on future visits would be great; just get the changes from the last visit rather than the entire scrobble list again.