This was reported by DTF.ru with a link to Izvestia and TASS.
Yes, Russian users are currently unable to upgrade Windows 10 to Windows 11 via Windows Update — instead, the system redirects them to the official Microsoft site, where when they try to download the update, a blank page opens. Russians are also unable to update Windows 11 to the current version 22H2, which was released a few days ago.
Of course, it could also be just a technical failure, but Russian users can get updates through a VPN if they change their IP address to a European or American one. This is not the first time Russians have had such problems with Windows this year — at the beginning of summer, they lost the ability to download an ISO image of the system from the official website.