Sure, but none of this points to high-performance languages being a shrinking niche. They will continue to dominate low-level code and library code.
Less low-level code will be written each year than high-level code, but it'll still be tremendously important. And as machines change, the underlying libraries will keep changing.
On the one hand, we have required effort. On the other hand, we have impact. To take an extreme example, Web browsers are a tiny niche in terms of development effort. Their impact however is something else entirely.
This is what I predict with low-level stuff. It will grow in terms of impact, but shrink in terms of development effort (at least in relative terms).
> as machines change, the underlying libraries will keep changing.
Increasingly, no they won't. What will change will be the optimization technique that we will need to operate on otherwise clean, elegant, obvious, and slow code.
Take a C library for instance. If it is written in a portable fashion, you only need to write a new C back-end to port that library to another machine. The same goes for semi-manually optimized code. You don't need to change the specification (I mean, the source code) to port the thing to another platform. You only need to change the optimization strategy. It's still an effort, but that's much less effort than a complete rewrite.
Less low-level code will be written each year than high-level code, but it'll still be tremendously important. And as machines change, the underlying libraries will keep changing.