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C++ has bad error messages because of language design. Contemporary C++ compilers are very good at reporting clear error messages about common mistakes, but template heavy code still yields arcane error messages. Templates are untyped, so there is no way to give sensible error messages when defining or instantiating a template. Instead you have to typecheck after template expansion, at which point you are left with an error message about compiler generated code.

There are some proposals which address this (e.g., concepts), but none of them are part of the language standard yet. Concepts in particular made it into the C++20 draft, but they also made it into a draft of the C++17 standard and were ultimately rejected. Somewhat vexingly C++ concepts actually come with the same problems only at the level of concepts instead of at the level of templates.