But being realistic, i dont think any non-GC´ed language has a chance to become the next corporate darling as Java is now.
In that sense, Go, Swift, C#, etc are much more fit to become the next kings in this area, and even them will do it very, very slowly.
The script family of languages also dont make a good fit, giving they tend to be bad at creating big, performant and constantly evolving kind of programs (Javascript, Python, etc).
I guess the languages which are AOT compiled, GC´ed and mostly objected oriented with some mix of FP will probably be more of a fit the take the crown jewels of the king Java.
The problem Rust will face in this scenario, is that it requires people with a level of brain power that contrary to 'high tech' is not that much available in the corporate level, (and the ones that have dont want to spend all of their lives behind a computer screen).
And also is a "productivity hog", when we compare to sophisticated languages like C# or Swift, as productivity in Rust is on par with C++, which is not good enough when compared even with the verbose and over-enginered Java codebase.
It´s basically the same reasons why, C++ is not the prefered language there. And i dont think just using the magic word 'safe' will have any charm for this kind of crowd. Giving while Rust can use this trick against C and C++, it doesnt work for productivity minded languages like Go, Kotlin, Swift and C#.
Mind you that modern GC´ed languages are pretty safe, and also pretty fast. So it will be very hard to convince the corporate layer to use a language where there will be scarcity of labor, and that means they will have to pay more and be able to have less employees.
The smartphone revolution gave performant and resource aware languages a renaissance and Rust is surfing in this wave. Rust has a lot of chance in smartphone, embedded, libraries and utilities and even in specific scenarios on the server.
But even for the "rewrite all in Rust" mantra for C++ (a language Rust is competitive with) it will stop going forward, giving the Unix, C and C++ codebases are pretty much very influential and with a lot of sophisticated and complex stuff already out there.
Anyway, i dont understand this urge to use just one language for everything. I think this is unrealistic and illusory, and i think its a better approach to elect two or three languages with fitness in some fields and just use them.
The "one language to rule them all" was already the Java approach since the nineties, and while it make it a very popular language, it was in a time where the competition were not that great and even then, it proved to not work really well in all scenarios (and i think thats a good thing because it means we are free from a computer language monopoly, which would slow down the evolution in the field).