Exactly: tsc was “slow enough to be painful” in the context of the 2.5Mloc codebase of VScode.
But it's not too slow for most people.
Likewise, Rust may be slow enough to be painful for some big projects that need to often rebuild from-scratch in release mode, but that niche is definitely much smaller than the size of the “rust compiles too slowly” crowd on HN.
I gave Rust classes in university a few years back, and literally none of my students complained about slow build times. At this point it's much more of an internet meme than an actual pain point for most devs.