Listen, if you're losing track of the date in your date picker as implied previously, then I don't know what to tell you man. Not a problem I've ever seen with progressive enhancement, and I've worked on more complex user interfaces than most. I have witnessed people struggle to solve state-related issues in SPAs for even relatively simple problems though, where the solution would be trivial in vanilla js. If it's not for the performance, and it's not cutting down development time, then what is the endless framework churn really accomplishing? Because that js date picker from twenty years ago still works.