But, for all the fangled cool things that the more powerful languages of yesteryears (like lisp), what seems to actually precipitate adoption is simply history, not necessarily expressiveness/powerful abstractions, etc. See C, sh and friends, javascript. Arguably, python is one where its ease made it popular and it continues to develop language wise, albeit not without controversy.
Currently about 7K lines into a python project and I'm getting more used to it but 'leaky abstractions' is a term that springs to mind at least 10 times per day if not more.
I'm busy with tricky array type conversions to feed stuff from one library into another a lot more than I would expect. Rather than that there is 'one way to do it' it seems there are about 50 of them, all incompatible with each other. Very messy at times.
My last statement referred to with python 3 and above, there is active development of the language's fundamental constructs. I guess there is active ES6 etc. C's newer standards aren't groundshakingly different from its original implementation.
Now hold on. The most successful sprog of nature is humanity[citation needed] and we're a case study in the fact that raw intelligence is more effective than fitness for any particular niche. So: as in nature, there may be a bunch of niche languages, but in time they'll find themselves with a conservation status while a smart language rules the earth.
Now, this is an important observation, but it needs one caveat - "fittest for its environment" != "fittest for the stated purpose". I.e. an objectively better tool may lose to a tool that's barely good enough, but e.g. provides a better CYA for managers, in a self-reinforcing loop of popularity.
That's the essence of Worse is Better - shit that's barely good enough will outcompete proper solutions.
(For many, that essay seems to be an ideal to follow; for me personally, it's just the description of the sad state of reality that we need to learn to work around.)
true = \x.\y.x
false = \x.\y.y