Dropping vecs that contain strings does not make any Rust code in the real world slow. You would need to have a vec containing billions of strings, occupying several gigs of memory, before dropping such a structure took any perceptible amount of time. And for extreme cases like that, you can simply use arenas. The bumpalo crate is approximately as old as Zig is. The reason that people so rarely turn to arenas in Rust isn't because you can't do them, because you've always been able to, but rather because arenas are a very specific solution to a specific sort of memory access pattern, and going out of your way to strictly adhere to that pattern doesn't produce measurable differences for most software.