Perhaps someone already mentioned this elsewhere, but nothing forces you to use only a single shell. A shell, after all, is just a running process. Yoh can even launch it from another shell.

As a GNU screen user already, I can imaginr having one of my default windows that load when I launch screen be nushell if I was so inclined. I can keep the rest as my default (e.g., bash or htop or whatever else I wany running there).