It’s neither simpler nor clearer to programmers that have experience with concepts, which already exist. They are designed to provide exactly what you’re asking for. You should spend some time looking into them.
In particular, you can easily create an `is_container` concept from your `Container` base class template, should you like. An off-the-cuff version is like https://godbolt.org/z/jYj7W8.
Luke
Ok but keep it clean and simple then because in 10 years from
now, C++ will be 10x more complex.