For people like me who actually buy things on itch and use it regularly, having upwards of 2000 items added to the library would make it unreasonably tedious and difficult to navigate. Until the ability to search and sort libraries is improved, keeping it functionally useable takes priority over some collector's need to demonstrate ownership of every single thing included in a $5 bundle explicitly organized for charity. Priority is the operative word there.
Viewing post in The new palestine bundle bundle page issues
https://itch.io/my-collections has terrible coding, that coding is not going to get better if the solution is to only have 3 or 4 games.
my prefered way to search for a game in my itch library right now is to simply hit the main page and search then click on the you own it banner to download. also chrome/tabs outliner can be used to create a sort of favorites list, then there is always ITAD.