That’s because the default model is designed for the general user. If you sat down and really worked with the documentation, you would realize you shouldn’t be using decks or collections for management you should be using tags. Decks and collections are a different abstraction for different purposes.

I’m in medical school which has basically mastered Anki. The AnKing deck, used by over a million medical students, has over 35,000 cards, cross-tagged by numerous study resources that exists on a single “deck” which receives regular updates. I regularly run basically instant queries on over 40,000+ cards.

Medical school Anki has basically mastered this workflow and the original commenters complaints are completely wrong/come from a misunderstanding of Anki’s data model.

To be put simply, ignoring subdecks, filtered decks, cards vs notes, etc.: cards can only belong to one deck, but can have multiple tags. What exactly do you want to see differently in the data model?