Just to make things more concrete. The Tab view used to easily show up to 9 credit card or identity items — now it can only show four items total. Thus, users who have more than 4 items in the card/identity category now will always have to use the scroll bar before they can autofill:
In essence, this doubles the amount of work required to autofill card or identity data. This is an especially troublesome loss of functionality and efficiency, given the lack of a keyboard shortcut for autofilling cards and identities.
As noted in the GitHub issue posted by @Protechted above, the number of vault entries displayed when in Vault view or Search results has now been reduced by one-third, from 11 items to only 7 items. How is this an improvement?