As a C++ dev, compiler explorer has been a great tool. Not only for quick checks, or playing around with new C++ features via small programs; even for code reviews it's a great way to show why doing something in a particular way is better via a snippet on compiler explorer.

I am in the same industry as Matt, and at my firm we use it a lot, all the time, to discuss things related to C++ features, and sometimes the quirks of the language/compilers.