Seeing "We couldn't sign you in" when trying to log in to Azure Portal from any account

I'm setting up a brand new installation of Windows for development activities. I've got most of my normal software installed -- nothing out of the ordinary has been added; nothing that has caused me trouble on any other computers.

I'm now finding that I'm stuck in a login loop on the Azure Portal. I start with the standard Microsoft Account login prompt, where I enter my username, then password, then OTP code. After that, I see the Azure logo where I can also observe my browser redirecting back and forth between the login.microsoftonline.com domain and the portal.azure.com domain. Eventually, It will stop and display the unhelpful text, "We couldn't sign you in. Please try again," on the login screen.

Things I've tried to solve this problem:

The problem seems localized just to this Windows device, however. The other Windows device still works fine if I log out and back in. And other services, such as Azure DevOps, and account.microsoft.com, work just fine.

I'm really baffled by this, and am not looking forward to reinstalling Windows 11 and all my dev tools again if that's the only solution we can come up with. I feel the operating system environment should not have this sort of impact on a website login flow...