a reinstallation will solve this issue just for a limit time, if micrsoft does'nt fix it. The main issue based upon the indexing process, who maybe blocks or do everything other with outlook. This is not especially an windows 11 issue - i had experienced similar issues in several Windows 10 environment's.
In Windows 11, microsoft had extend the indexing and the usage of them. It seems, that the interlock between outlooks database files and the indexing service should be the root of the issue. If you remove outlook from the index service (in the german windows11 : systemsteuerung->alle systemelemente->indexoptionen->indizierte Orte), immediately, the issue is gone. The backsite of the of the coin is, that the search process in outlook, will be quite slower.
Generaly, microsoft needs to fix it finaly.
A windows reinstallation is not required. A new profile of the mail-accounts will not solve the issue. A temporary solution could be drop the index content. This helps not finaly for alonger term.
I will live with the search penalty in outlook, as long as microsoft had fixed them.