I agree!
I dislike the way that itch forces all buyers to add (large) bundle items individually.
As a buyer, I should be the one who decides if I want to "flood my library with purchased games".
I had this same problem with the bundle for Racial Equality awhile back, and the way staff was so dismissive of even considering the " add all" option was why I've never spent any more money here since then.
Staff, if folks can write userscripts to claim all items then surely one of your coders could make this an option for your customers!