Not when you called templated functions and were greeted with compile-time template stack traces. Or you called overloaded functions and were presented with 50 alternatives you might have meant. The language is inherently unfriendly to user-friendly error messages.
In my opinion, the complexity of the interactions between C++'s {preprocessor, overload resolution, template resolution, operator overloading, and implicit casting} can make it really hard to know the meaning of a code snippet you're looking at.
If people use these features only in a very limited, disciplined manner it can be okay.
But on projects where they don't, by golly it's a mess.
(I suppose it's possible to write a horrible mess in any language, so maybe it's unfair for me to pick on C++.)
I’m talking about C++. You wrote that Clang already had friendly error messages. While they were less unfriendly than GCC, calling them friendly is a stretch.
Rust having traits instead of templates is a big ergonomic improvement in that area.
Funnily enough, trait bounds are still a big pain in the neck to provide good diagnostics for because of the amount of things that need to be tracked that are cross cutting across stages of the compiler that under normal operation don't need to talk to each other. They got better in 2018, as async/await put them even more front and center and focused some attention on them, and a lot of work for keeping additional metadata around was added since then (search the codebase for enum ObligationCauseCode if you're curious) to improve them. Now with the new "next" trait solver they have a chance to get even better.
It still easier than providing good diagnostics for template errors though :) (althought I'm convinced that if addressing those errors was high priority, common cases of template instantiations could be modeled internally in the same way as traits purely for diagnostics and materially improve the situation — I understand why it hasn't happened, it is hard and not obviously important).
