When bulk deleting 20 items, the modal to confirm deletion counts down from 20 while deleting. I'd expect a loading state and/or for the number to not change.

Replication steps

1. Test on a site with at least 100+ pages. Here's a playground link that will spin up a version.
2. Open the Site Editor > Pages.
3. Switch to Grid layout.
4. Bulk edit and select all.
5. Move the items to trash.
6. Notice the modal counts down from 20.

Video:

Environment

WP 6.6.1, GB 18.9, Chrome.