My experience with libraries built by the community. Libraries for react have much higher quality than angular libraries. I usually fix the hard bugs in our team, and therefore read a lot of library code on GitHub. Usually react libraries impress me and angular libraries are often rather underwhelming. Highly subjective opinion though.
I don't have much experience outside of Angular ecosystem, but I share this sentiment too - the framework might be good, but the community size and quality also matter a lot. A similar example would be Sublime Text vs VSCode - I use the former, but VSCode has so much more vibrant community and everything supports VSCode by default, unlike ST where you are lucky to get a half-working prototype.
First of all, if you want to compare actual growth, you'll need a logarithmic scale. Second, if you add in alternatives like Vue.js, you'll realize React dwarfs both Angular and Vue.js, yet I don't see anyone on HN claiming "Vue is dying".
How so?