Yeah, I think was algebraic + pattern matching that break the ghetto. Suddenly types were far more useful without going crazy like Haskell!
P.D: Before, the exposure of types was from C++/Java, and special C++ is always a horrible exponent of anything except how make a overly complex language.
Once you see what good application of types look like, is far better sell!
Functional programmers keep hyping up ADTs like this but the normie programmer doesn't care about ADTs or immutability. What really brought back static types was Golang & typescript, both have local variable type inference, good IDE support & other tooling, and (at least superficially) lighter weight syntax than Java. Normies don't care about algebraic types, pattern matching, immutability, referencial trasparency, type classes. What matters is libraries and tooling.
P.D: Before, the exposure of types was from C++/Java, and special C++ is always a horrible exponent of anything except how make a overly complex language.
Once you see what good application of types look like, is far better sell!