One thing that is still horrific (imho) is unicode support. Last time I found that in order to print unicode strings with cross platform support on a simple way I required a boost library [1]. The dichotomy between standard and "wide" string APIs is kind of a mess.

Also, construction, destruction and move semantics makes everything really complicated and even simple baseline code requires a bunch of boilerplate [2].

1: https://www.boost.org/doc/libs/develop/libs/nowide/doc/html/...

2: https://gist.github.com/EmmanuelOga/12e1da5aedd9f6dc50e742cd...