In modern C++, you get the same benefits as are claimed for "lifetime annotations" by operating at a higher level. In effect, a library may adopt responsibility for what the Rust compiler would have enforced, and where it matters, they routinely do. This is no substantial burden. As a result, it has been a very long time since I last encountered a lifetime problem in my C++ code. Sum types work fine in C++. Pattern matching is an extra notational convenience on top of them.

Rust has many nice convenience features, but lacks numerous other powerful features C++ provides. But this is not a good place to go into detail. If you care, there is plenty of material online. The point remains that comparisons, if done at all, should be done based on knowledge about current facts, not suppositions and hearsay.