> Poor performance. Usually, it is significantly more efficient to allocate and free resources in batches.

This one is big. It is a lot of accounting work to individually allocate and deallocate a lot of objects.

The Zig approach is to force you to decide on and write all of your allocation and deallocation code, which I found leads to more performant code almost by default – Rust is explicitly leaving that on the table. C obviously works the same way, but doesn't have an arena allocator in the standard library.

Re: C++ vs Rust, it might be more of a pain in Rust because of this: https://news.ycombinator.com/item?id=33637092