I'm sure the Wikipedia mods have many great, valid reasons for deleting articles. Unfortunately for the ignorant masses, this has bad optics, since it looks like it runs counter to their goal of "cataloging all human knowledge".
For example: if I move my email off Gmail, how to archive my YouTube notification emails? I worry about that and I just can't get myself to realize it's a non-problem and I can just delete them. There could be some historical value in an archive of YouTube notification emails over 20 years but (unfortunately for future historians studying YouTube) the weight of carrying those around us not worth the low expected value. Even though the reason I put them in their own folder was to declutter my inbox, not to archive them!