Like what? Vue.js? One BDFL who might take a new job or be hired away by BigCo? Some other starving artist project that will die when the main contributor loses interest perhaps?
GPL, done well, fosters community and contributions. In five years, everything will be "legacy code" and it won't be nice maintaining something with no community behind it. Permissive licenses only work when backed by giants like Facebook/Google/Apple. Even then, they can go Angular 1 on you.
Dead stack with no community is a forced rewrite. You can't just sit on it, because every new feature has to be done from scratch by yourself. That's not a lot of fun in my experience.
I haven't seen (A)GPL done well and sucessfully in the (frontend) webdev space. I think some of the bigger component libraries are AGPL + commercial license, but they don't seem to have much in the way of community contributing, and would likely be just as successful if they were entirely closed.
If the commercial entity behind a dual-licensed project fails, will those that bought a commercial version contribute to its survival? Can they without licensing issues?
And preact seems simple enough that if there weren't X other JS frameworks, or if there is a specific niche only it fills, a lot of projects would try to clone it with a less restrictive license, probably win the mindshare race, and be the ones with a community that contributes, regardless of technical merit.
I might be wrong, I might be missing some shining counter-example, but I just don't see it happening in that space, as much as there are arguments why it would be in everybodies interest to make it succeed.
