I think two-way binding going by the way side because developers are tired of having to deal with unintended loop backs. You start having to add weird flags to your data to indicate that data changes were the result of user actions and not changes from the backend to avoid endless event loops. Two-way binding results in more code that's buggier whereas one-way binding with actions results in much more organized and understandable code with none of the unintended consequences.
I'm thinking that's a framework-specific or coding-style issue? From using a number of frameworks, I've virtually never had issues with endless loops. Perhaps it helps that frameworks like Knockout, etc don't trigger change events when the value is the same.
