I've worked on quite a few projects that would have had significantly worse user experiences if they were done in a purely SSR driven way: * Chat applications,

I've worked on quite a few projects that would have had significantly worse user experiences if they were done in a purely SSR driven way: * Chat applications, or anything where you need to have the UI react to incoming events from a socket. * Applications where sensitive data lives in the client and you don't want to be liable for that passing through your servers. * Anything dealing with video or audio (e.g. video chat, screen recordings.) * Applications that are driven by peer to peer data. * Applications with high interactivity (e.g. spreadsheets, heavy form validation, drag and drop UIs, graphic manipulation.) It really depends on what your application is doing. If you're just a blog or an eCommerce site, it's definitely worth asking if you need a frontend framework. But for some applications it's absolutely worth it.