I can speak from my personal experience which might not be applicable to everyone.
I started with Blaze because it was super easy to get into. But as my code base got bigger I found myself wiring a lot of repetitive HTML code, so I decided to do heavy refactoring to abstract and create reusable components. At the same time react was getting popular and provided a clear APIs on how to create components and manage their life cycle, it was solving the issue I was facing so I decided it’s better to switch.
I’ve not used Blaze components so I can’t comment on those but for me I see two clear benefits with react:
- Clear API with props and lifecycle management methods and stage management
- Tons of reusable components on npmjs
And since I was early on my project I thought the two points above are sufficient to justify the switch. However if you’ve a working project with all the components you need, that Blaze will surely do the job as well, I’m not a fan of switching tech and chasing hype, we need to deliver value and ship products to end users and customers, but for me, React was clearly solving a problem I was facing when attempting to scale my front-end code.
I hope that helps.