Browsers could still do something about mixed Internet and LAN/Localhost requests by IP address regardless of the domain name.

Did you misread the post?

They're doing this because the localhost shenanigans got blocked. This is pure internet requests, but the IP changes (or fails to resolve) based on what's in your hosts file.

This does not request a local/LAN file, it's a remote server but without any DNS entry unless the hosts file entry is present.