[ignaloidas]

From my experience it's a lot easier to learn another language than to learn a new model of operation or new concepts entirely. And if you'll want to work with Godot, that will likely be the main barrier, and the main thing that will not be transferable to other contexts. The language however, can only make working with the concepts easier or harder. Godot team has decided that having their own language designed for dealing with the concepts of the engine makes it easier to use and results in less work than trying to adapt some existing language to the concepts of the engine. I've dealt with this a couple times, where a language was transformed so much by the context it was used in, it felt like an entirely different language.

[Jach]

On your last point, even just a language like JavaScript (or even Java) has, over long enough periods of time, evolved to accumulate enough new features and common idioms that if you look at typical code from the 90s vs now in those languages, it's not hard to picture entirely different languages. And engineers are expected to just learn the new changes and keep on, much as they're expected to just learn algorithms, libraries, test frameworks, other domain specific frameworks that come and go, database stuff, profiling and other monitoring methods, security concerns, how not to violate the GDPR, ....

But suggest a different language or a DSL for something, no matter how much sense it makes (sometimes getting simple SQL in places is a political struggle, and it's unfortunate when teams develop a "regex expert" even though all the regexes are simple), even one that is already super similar to one they already know like GDScript and so is rather trivial to learn (no one's asking you to learn something on the order of complexity and different-to-others like Haskell here), and devs start putting their foot down and saying "Of all the things, I"m not learning that!"