I recently had to set up a Windows 11 pc in S mode, and they needed S mode disabled to install Quickbooks. S mode could only be disabled through the Microsoft Store, and it wouldn't let me access the Microsoft Store at all without creating a Microsoft account. Eventually I managed to disable S mode by booting recovery media, and making registry edits from the command line there.

Now that the machine is out of S mode, it lets me access the Microsoft store without an account for free apps. But from inside S mode (which many PCs ship with) it would not let me access the store at all without an account. It's also worth mentioning that you have to intentionally avoid connecting the computer to the internet during the initial set up, or it will require you to create a Microsoft account to use the PC at all.