"No more [...] slow compile times with complex ownership tracking."
Presumably this is referring to Rust, which has a borrow checker and slow compile times. The author is, I assume, under the common misconception that these facts are closely related. They're not; I think the borrow checker runs in linear time though I can't find confirmation of this, and in any event profiling reveals that it only accounts for a small fraction of compile times. Rust compile times are slow because the language has a bunch of other non-borrow-checking-related features that trade off compilation speed for other desiderata (monomorphization, LLVM optimization, procedural macros, crates as a translation unit). Also because the rustc codebase is huge and fairly arcane and not that many people understand it well, and while there's a lot of room for improvement in principle it's mostly not low-hanging fruit, requiring major architectural changes, so it'd require a large investment of resources which no one has put up.
Presumably this is referring to Rust, which has a borrow checker and slow compile times. The author is, I assume, under the common misconception that these facts are closely related. They're not; I think the borrow checker runs in linear time though I can't find confirmation of this, and in any event profiling reveals that it only accounts for a small fraction of compile times. Rust compile times are slow because the language has a bunch of other non-borrow-checking-related features that trade off compilation speed for other desiderata (monomorphization, LLVM optimization, procedural macros, crates as a translation unit). Also because the rustc codebase is huge and fairly arcane and not that many people understand it well, and while there's a lot of room for improvement in principle it's mostly not low-hanging fruit, requiring major architectural changes, so it'd require a large investment of resources which no one has put up.