But, sadly, OP is right.

When doing a technical screen I'll sometimes pick a skill the person claims to have, and ask them the simplest possible non-trivial question I can ask.

For example, let's say you list 'SQL' as one of the skills on your CV. I might show you a SQL statement like:

  SELECT id, start_date FROM employees;

I'll tell you id is an auto-increment field, and ask whether the result would show the newest employee at the top or the bottom.

You have a 50/50 chance of getting it right. If you get it wrong, I'll tell you the answer. Getting it wrong wouldn't disqualify you.

Then I'll ask you how to get it in the opposite order.

I am expecting you to immediately say 'add DESC'. If you can't answer that question in under 2 seconds, you probably haven't written enough SQL to justify listing it as a skill on your CV.

You would be surprised at how many people fail simple tests just like this one.

(I won't use this particular one again.)