It's extremely common for people to not only advertise that they have specific skills, but even to have been using those skills for years, yet be entirely unable to demonstrate those skills when requested.

C++ is a particularly badly affected language for some reason. I think there are a lot of people who learned C++ once, a long time ago, then moved to Java as quickly as they could when it came out. But nobody likes to admit that maybe they lost a skill they once had, so they keep putting it down on the CV regardless. And then when asked to write something like hello world, they don't remember how to use std::cout or whatever.

I honestly don't know. I asked myself the same question.

These guys are applying for C++ dev jobs but are completely unable to write a program. Most of these fake programmers have studied electronics (not CS) or have studied in a country where you can buy a degree.