> Because any language feature that is objectively good with no downside or trade-off has already been implemented in some popular language somewhere.
This almost implies that there is no opportunity for anything new in programming language research, which I find laughably depressing, especially if you take "some popular language somewhere" to mean the popular industrial languages. It would be rather sad to think that Java (or C++, or C#, or Ruby, or Python, ...) represents the pinacle of programming language design, and we're stuck with it and its ilk from now on, forever, since there are no good language features left that are worth implementing.
It doesn't imply that. But I think the idea that programming language research always entails esoteric new, from scatch, languages with no tools is even more depressing. There has been a lot of research over thr last 5 decades and every year more of that research gets put to use. It wasn't that long ago that a cross platform language that gets dynamically compiled to native code and supports efficient garbage collection would be considered science fiction.
Progress is ongongoing but it's evolutionary not revolutionary - and that is a good thing.
This almost implies that there is no opportunity for anything new in programming language research, which I find laughably depressing, especially if you take "some popular language somewhere" to mean the popular industrial languages. It would be rather sad to think that Java (or C++, or C#, or Ruby, or Python, ...) represents the pinacle of programming language design, and we're stuck with it and its ilk from now on, forever, since there are no good language features left that are worth implementing.