[cataphract]

There have been type-erasure libraries in c++ for a longish time that allow choosing inline vtables and inline storage. It's definitely been a widely talked about technique for at least 10 years (I see talks about Dyno from 2017).

[gignico]

Well, Rust as well has been around for more than 10 years now. I don't imply Rust invented the approach. Surely academia knew about it decades before. I was rather commenting on how one's mental model of things can change by learning new languages.