I have the same change to 'Sign out' as the OP and just noticed it today. I found this thread while searching for news about this change. Windows 11 Home with the same version, OS build and Windows Feature Experience Pack as the OP. In my case the installation date is recorded as 10/10/2022.
Like the OP, I don't see this as an improvement. Before I realised that 'Sign out' was hidden behind the three dots, I had to resort to <CTRL><ALT><DEL> to bring up 'Switch user' and 'Sign out'.