To increase or decrease the number of items that show in recent or pinned for Remote Desktop we have to use regedit.
If you want to do it for all the users go:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced
and edit or add the DWORD value if it doesn’t exist
JumpListItems_Maximum
Set the convenient value for you, like 10 or 20 in decimal.
Close regedit and it should be it. Otherwise restart windows explorer or sign out and sign it.