> [...] from what I understand, has Ackermann complexity rather than EXPTIME.
Really bad worst case times aren't necessarily bad in practice, if most instances you actually encounter can be solved quickly (especially if you are happy to be satisfied with worse than proven-optimal solutions.)
Compare how Hindley-Milner type inference, which forms the basis of Rust's or Haskell's type systems, is double-exponential in the worst case (or something like that), but typically fast in practice.
Really bad worst case times aren't necessarily bad in practice, if most instances you actually encounter can be solved quickly (especially if you are happy to be satisfied with worse than proven-optimal solutions.)
Compare how Hindley-Milner type inference, which forms the basis of Rust's or Haskell's type systems, is double-exponential in the worst case (or something like that), but typically fast in practice.