This hasn’t been fixed in ~3 months so I went ahead and filed an issue with the ag-grid developers in case they just aren’t aware of the problem. I has previously assumed this was a pending change on their end, but can’t find an issue for it, so its possible I misremembered.
The Inventor issue is here: Mobile Device Pagination Bar Rendering Issues · Issue #9239 · ag-grid/ag-grid · GitHub
I’ll leave the thread open here for now.