Hi, I'm not sure any change is needed to Start11. It is getting this information from Windows 11, so turning it off there should be all that is needed. The following is working for me:
1. Go into Settings > Personalization > Start
2. Turn off "Show Recently opened items in Start, Jump Lists, and File Explorer"
3. (Not sure if this bit is needed but to be sure that anything present is cleared). Open Explorer > right click on quick Access and select Options, then select General tab if not already selected.
4. from Drop Down Menu select Quick Access then press the Clear button in Privacy
5. From the Down Menu select This PC then press the Clear button in Privacy.
6. Change the Open File Explorer setting is back to its original value and press Apply
7. Now go to the Start11 Menu. If it still has items on the Recent then right click on one of them and choose "remove from list" that should remove everything from the Start11 list.
8. When you open a new document of some sort it should not now appear on the Start11 menu