I did it last week, but it was a bit hard to navigate through the automated phone system as it's so geared up to Windows 10/11.

Hah, the local line here still has something like "Press 1 for Windows 10/11, press 2 for Windows 7/8/8.1, press 3 for older versions".

I activated Office XP on Windows 98 over the phone a while ago on my Pentium III machine.