My experience with migrating real-world projects incrementally from C++98 -> C++20 has been that it is typically closer to a day of work to get everything worki

My experience with migrating real-world projects incrementally from C++98 -> C++20 has been that it is typically closer to a day of work to get everything working with the new standard, and that the benefits have been enormous. `if constexpr` is a particularly standout example of something which has turned things which would have been a week's worth from a C++ expert into something doable in an hour by a junior developer.