People focus on frameworks and popularity, but as someone who builds a lot of complex front ends, what really matters to me is architecture--architectural simplicity and architectural scalability.
Before trying React/Redux, I was against js frameworks too. They all seemed to add a whole extra layer of unnecessary mutable state to keep in sync, and required lots of cruft and duplication. Just give me coffeescript, underscore, and jquery, thank you very much. I composed nice little modular components that latched on to server-generated html, kept state to a minimum, and used a global event bus to deal with interdependence. It had some warts, but it got the job done and scaled up reasonably well. It certainly beat procedural jquery spaghetti and I thought it beat the current crop of frameworks too--what it lacked in polish, community, and standardization were made up for by modularity and simplicity.
Of course, then I discovered React, and more recently, Redux. I immediately realized that it was the culmination of what I'd been trying to do all along. It was basically the same idea, but battle-tested, standardized, and infinitely more elegant. So why wouldn't I use it? Sure, there was a learning curve while I got used to other people's way of thinking about and expressing these concepts. Rather than designing the system myself and knowing it like the back of my hand, I had to learn a whole new vocabulary and toolchain. But it was so, so worth it in the end. I'm still building apps with an architecture I believe in, and I get all the benefits of a well-supported framework to boot.
So, to finally get back to the central point: never once was popularity an important factor in my decisions, and I suspect this is also the case for many many others who adopt one framework or another. Not everything that's popular is only popular due to a bandwagon effect--sometimes the shiny new thing really is a big step forward.