I have SharePoint online list with about 6500 items. One column is an indexed choice column with about six choices. If I create a modern grouped view, grouped on this choice column, the item count for each group shows the number in that group, but only up to the item limit set in the view properties. If I increase the item limit up to 4999, then the grouped view's item count increases up to this limit (still doesn't show all because there are 6500 total items) and the view then takes an extremely long time to load (unusable). Increasing the item limit to from 4999 to 5001 causes the "something went wrong" error, presumably because the list view threshold was exceeded even though the columns involved in the view are indexed.
So my question is, how can a grouped view be provisioned on a large list so that the item count makes some kind of sense (i.e. like not showing it all in this case)? Showing a list with 6500 items, grouped by six categories that each show an item count that totals 36 is quite misleading to everyone who looks at it.