If people don’t have time to keep up with a languages updates (which, in case of C++, is currently _once_ every three years), then they don’t have time to complain about the lack of features, either. This one had the time to complain and just didn’t want to bother typing "c++ string formatting", which would have been fewer keystrokes than the comment complaining.
On DuckDuckGo, the very first result for "c++ string formatting" is the exact thing this person was complaining about.
