Nothing in the post you're replying to is about "is 2000 passkeys storable", it's about "if I have 2000 passkeys and I need to move between an Apple device and an Android device, do I need to establish a second set of 2000 passkeys"?

Did you not read the comment thread you're responding to?

Dunno why the downvotes, if you're willing to trust Apple or Google this is a good method for passkey usage. because your touchID/faceid/opticalid auth gate the keyring's on either of these vendors your passkey works without having to migrate them. EDIT: Also ANY device that you add to your iCloud has access to the passkeys you've made... it's a dream for secure access.