It's already there, just under a different paradigm.
auto parameters make this easy to write, particularly for lambdas.
FILETIME to a C++ clock like std::system_clock or winrt::clock?
The winrt::clock has a conversion for you.
If they aren't shown, then they aren't automatable, so there's no requirement that they exist in the UI automation tree.
The critical section may be an old dog, but it's still learning new tricks.
What would make it an illegal base class?
That's fine, since you're not closing the handle that you're waiting on.
Adding another level of indirection.
You can put your own object in the surrogate first.
std::apply figure out which overload I intend to use? Only one of then will work!
The overload resolution happens before the compiler knows what it's going to be used for.