This is so true. I see a lot of job ads that seem to require very specific experience, but where anyone in that field could do the job.
If you just make up eg 4 different types of technology, and put a few things in each bracket:
[SVN, Git, Mercurial, CVS]
[MySQL, PostgreSQL, Oracle, MSSQL]
[AMQP, MQTT, STOMP, RabbitMQ]
[Java, C#, C++, ObjC]
Now if someone came along and said they'd solved a domain problem (eg trading systems) with one of each of those, I would more or less believe they could do it with any of the others, with a bit of time to get used to things (particularly c++).
But if you don't believe that, ie if you decide the person must have a specific combination, then you've just shattered the potential pool of applicants into 256 little pieces.
The other thing that annoys me is the pettiness of the interview questions. So many things that you could easily google can be used to stump anyone. What's the default implementation of GetHash() in c#? I actually got asked this once.
Then there's the other way to do things, which is to do an online coding assessment. I guess this gets rid of the FizzBuzz failures, but it tends to be a problem that's too small to see if you're about to dig a hole.