Speaking as a mid-career who does know better, the thing is that I still have to compete in said competitive market along with everyone else and lots of recruiters/hiring managers/linkedin influencers/etc... don't seem to know better either.
I still remember the day I saw a posting for a job that required 10 years of Java, 5 Years of C#. At the time Java was about 8 years old, and C# about 3. I'll bet they hired someone anyway and nobody clued them into how impossible their requirement was.