Yes. It really is. A couple weeks ago I interviewed a self-described C# expert who claimed to know everything about C# but couldn't even begin to describe the difference between methods and fields and properties, and did not seem aware that methods have return types. I'm not sure he had ever written a line of real code in C#, or any other language for that matter. This was a recent CS grad from a reasonable quality engineering school, so I'm not sure how he even got through college.
And for the record, I try to interview people on their strengths, giving them the opportunity to show off what they know about the area where their greatest interest or experience lies. A shocking percentage of people (>50%) nevertheless fail to demonstrate even basic knowledge of syntax or language features in the language of their own choice. This is without even considering actual workplace skills like git, PR review, tickets, etc. as discussed above.
