I think the biggest thing going for Blaze is the amount of integration especially when paired with Meteor packaging system where you get front and back end code lumped into one piece.
Am I too old or has everybody forgotten meteor-useraccounts?
The fact that you can spin an entire authentication system with all of the routes and UI in one go is unparalleled. Maybe if you compare Blaze’s features with other tools on the market it’d appear lacking but hey even if it’s I still would use it because it allows you to develop applications faster. I agree with what @acemtp brought up in Make Meteor great again
It’s about that tight level of integration that allows you to go much faster. It’s the sum of the tools rather every piece on its own. And that’s what made me choose Meteor and continue using it to this day. I hope Meteor continues in such direction.
Don’t fall in love with your tools; It’s never about the tools it’s about solving problems for users in a timely manner and I still cannot find a single user who can distinguish whether your application is built with React or Blaze or Fortran.