The ultimate power that can actually be manifested in physical reality (as far as we know) is still Turing Machines[1]... the rest is mostly ergonomics.
[1] Well, QM may add a "little bit" of efficiency, but it doesn't add any oracular power, per se. AFAIUI, at least.
And a lot of it is embedding FORTRAN or COBOL in the new pretty C/++.
New skin, same system.
In Julia, too.
Whose permission do you seek who will "let you" or not "let you" write a critical system in some new relatively unknown language? What if you work for yourself or are creating a startup?
[1] I think it's spelled that way these days, but of course given the context of the thread, maybe you're talking about old-school FORTRAN.