[eru]

Algebraic data structures mostly just means union types.

(That's the + in the algebra. The * comes from bundling multiple values together, like in a tuple or in a C-style record, virtually all languages already have that.)

There's also Generalized Algebraic Datatypes (GADT). They are a bit more complicated. So I don't expect mainstream languages to pick them up anytime soon.

About GC: you _can_ do pure functional programming without a GC. But it requires lots of big guns from more advanced theory. (Mostly stuff like linear typing.) However imperative programming without a GC is comparatively simple.

So it's no wonder that historically, GC was invented for FP first, and GC-free FP was only discovered later.

(And for general CRUD or web programming, or basically anything outside of low level systems programming, GC is more productive in terms of programmer time than other approaches. At least given currently known techniques.)