With discovery disabled in xmlui, a recently submitted item does not show on the recently submitted items list for the collection or community page, until the page cache expires. This may be by design, but it is a route that a user may be expecting to find their recently submitted item.
Perhaps on submission, the cache for the parent container pages can be invalidated so that the next page view of it will get the recently submitted item in the list.
To reproduce, in xmlui (tested with discovery off), view a collection page, then submit a new item to that collection, and go back to that collection page after submission. Continuously refreshing the page will not show the new item, unless a user tries to hard-clear the xmlui cache. Such as appending junk to the url as a parameter. i.e. servername.com/handle/123456789/1234?random-text