Spoken like someone who's never taken the time ie. years to become proficient at anything. OP clearly hasn't a clue what the difference is between competent and expert is.

It is true that the current state of IT is so fluid that it's hard to justify devoting the time and energy on a single programming language to attain wizard status, assuming you're looking for work that is. But anyone with a decade of programming under their belt can become 'good enough' in a new development platform in weeks because programming languages are like tools to a competent craftsman. I've known professional musicians that learned how to play an entirely new instrument in just a few weeks sufficiently well to perform. They never intend to become a virtuoso on the instrument, just good enough to get the job.

Besides it's a well known and understood phenomena that people with a some amount of experience with a new discipline -- any discipline, not just programming -- consider themselves considerably better than they actually are. It's not until they gather more experience that they begin to understand just how little they actually know. As the saying goes the path to true enlightenment starts when you realize that you know nothing.