It's not even about faster computers and storage, but just about better test techniques, and better written tests. You don't actually need very fast hardware for fast tests; you just need to spend some time on it. And roughly know what you're doing.

External dependencies (such as PostgreSQL, Redis, what-have-you) are a pain though. I feel pretty strongly that just a single command ("go test", "cargo test", "npm test", etc.) should run all the tests on all platforms, reliably, with a minimal of fuss and messing about. Things like docker-compose or whatnot quality as "a fuss and messing about".