But why is that an issue at all ? Having boost and other utilities is great. And since it's all templates there's in practice in your binary no added cost if you're using folly::foo or std::foo or boost::foo, you can pick and choose the exact data structures that allow exactly what you want (or write your own if you think that you can do a few percent better than folly of abseil in your specific use case).

If I was using java or python I'd definitely not use the standard things most of the time either because it's more than likely that there's a more efficient way in some other library, and because my main paycheck comes from "can you make this as fast as technically possible given this average consumer hardware"-problems