> Let's be clear: Rust is still far away from formal verification; the borrow checker won't save you from logical errors.

completely agree.

> Second, data structures like graphs, trees, hashmaps are well understood and have a lot of algorithms built on top of them.

well understood, yes, by authors of textbooks and papers. your average programmer may have understood them once, before he made it to the enterprise and started passing buckets of bits between http endpoints for a living.

> Algorithms with a lot of research behind them, and complexity analysis. While complexity analysis doesn't always equal performance, if I can't use these universal tools in your language, I'll probably think of it as a toy language which stops me from getting stuff done, which is still what most of us are paid for.

you can write a recursive data structure in Rust in the same way you'd write one in C++ - use unsafe pointers, even the asterisk is the same. nothing is stopping anyone from doing that, in fact there are lots of examples on crates.io and in the stdlib.

Your argument doesn’t make much sense. You can use unsafe and raw pointer to do EVERYTHING you can do in C/C++ and it will be just as safe as you write it in C/C+. And then, you can (ab)use the type system to make sure you or your team cannot use it in the wrong way.