I forgot to add &quot;<i>mostly</i> scarcely useful&quot;, instead of &quot;scarcely useful&quot;. There are some things that make sense, like file system library and async I&#x2F;O library that you&#x27;ve mentioned (althrough I don&#x27;t agree on concepts and modules, but that&#x27;s up to one&#x27;s preference), but then comes stuff like constexpr, rvalue reference, Deleted and Defaulted Functions, that aren&#x27;t essential to most programmers, and mostly just clutter the language, because only like, 1% will use them, and the rest will be like &quot;what the hell is this&quot; when looking at that 1%&#x27;s code.