I don't want. It is too easy. People will set it, and months later they
report that direct async processes won't work, and they've forgotten
this setting, and there's a new host which needs an interactive password.
You can achieve the same effect, if you set the connection-local profile
w/o any :protocol, :user or :machine, just the :application. Something like
--8<---------------cut here---------------start------------->8---
(connection-local-set-profiles
'(:application tramp) 'remote-direct-async-process)
--8<---------------cut here---------------end--------------->8---
And be prepared that I'll blame you in case you report an error because
of this 🙂