Just semantics, but I think the borrow checker is part of modernizing C++.

(The way to manage memory in C++ and C is to opt in to a memory management pattern... hopefully you've chosen a good pattern and hopefully you follow it consistently. Patterns are generally backed by utilities and primitives that are hopefully correct, complete, and hopefully make it relatively easy to follow the pattern consistently. Hopefully you can get a linter to help you too. In a sense Rust takes the same approach, but was implemented from the ground up to eliminate all the gaps so you essentially don't have to hope to successfully bridge the gaps yourself.)