I don't know. I still find Vaadin's pricing way over what I could spend on a startup project. But it could just be me.
edit: People also forget that Eclipse RAP still exists and although it's probably not that "modern", it works.
edit: People also forget that Eclipse RAP still exists and although it's probably not that "modern", it works.
Have you tried one of the latest versions?
Disclaimer: I work for Vaadin.
I don't pay for Vaadin, you don't need to unless you want the extra components, and even if you do it's affordable, much cheaper than building the same system in React.