You have to be disconnected from wifi and Ethernet to be offered the option of a local account. This was removed in 11.
I use Windows 11 Professional and was able to install using a local account while connected to WiFi.
I'm not sure why they consider that it makes any sense. Probably just a motherfucker higher-up who really like dark patterns and annoying their customers^W advertising targets, so MS can resell more private informations and they get a big bonus.