A good part of that reluctance is entirely rational.
There are many dozens of programming languages that might be worth learning based on what communities of current users say about them.
But you can't tell if they're really worth investing all over again what you already invested in other languages without, well, investing.
It's a lemon market. Sellers know more than you about the true value of the car, err, language, but they have incentive to tell you it's great. Even worse, with programming languages even the most honest sellers might not know how their language really stacks up to the ones you already know because by symmetry they are underinformed too.
For example, I tried getting into Smalltalk based on the intense hype coming from the community, but I came to suspect it really doesn't offer that much of an advantage over languages I know better and stopped. But maybe it really is better... I'll probably never know.