I’m very wary of putting my flashcards (about 25k in a bunch of decks stretching back nearly 20 years now) in something that either 1) I own fully (I’ve bought the software and it will work even if your company doesn’t); or 2) at least provide full-fidelity exports of not just the content but also the repetition history. It looks like a very well-done app and I agree that Anki can be clunky but I don’t worry about it…
Can you speak about how you use the 25k cards? Do you feel you retain them all?
At first glance i suspect you're using your 25k cards the way i envision my ideal knowledge base setup. A store of information which exceeds my brains capacity, but which i can choose a slice at which i want to transfer to my brain. Ie choose a deck of cards and working on that to transfer (learn) the material again.