I don't remember exactly why and how some shell scripts refused to run, but on top of my head I think 'alias' was not working and 'sudo !!' too.

I hope you're not trying to source regular Bash scripts without using source-bash.

I've used xonsh as my primary shell for many years now. The Bash compatibility was poor initially, but they fixed most/all the issues, and source-bash just works.

I use Gentoo, and don't actually use sudo, so I can't comment on that (I just su into root).

Interesting! I think I never tried to update xonsh in 7 years or so.