By following the guide to "Disable creation of personal lists" (https://docs.microsoft.com/en-us/sharepoint/control-lists) and set "Set-SPOTenant -DisablePersonalListCreation $true" users can't create Lists within Teams anymore.
The "Create" button is inactive. There's no valid reason why DisablePersonalListCreation has an impact on creating Lists within a Teams Channel where the list is saved in the SharePoint site of the M365 group which is assigned to the Teams.