Yes, not only Windows 10, but Windows 11.
I found the only way to stop it was to not use Windows Spotlight as my lock screen. I used a picture. When I tried Spotlight again a few days later, it was back to English. I am now waiting to see what happens, will it revert to another language again at some point?
Microsoft need to sort this, but as with all other issues, all they do is tell you to do some complicated change that never works. They do not care about us, their paying customers.