While this could be achieved on the frontend with jQuery + plugins (or even vanilla JS, let's be honest) I think you're not remembering how cumbersome and error-prone building forms / complicated flows was without a dedicated framework. Speaking from experience, I believe Backbone.js was the first time I felt confident building state based UI on the web. Newer frameworks (first Angular, then React/Vue since then) have upped the stakes.
Honestly, my problems as a developer generally aren't with the frameworks (I'm mostly defending Vue here, as I find it predictable and easy) but with the build tools, which have gotten a bit out of hand and always feel brittle.
Personally, I think the main problem with jQuery was .data instead of having proper state management. If we used jQuery just as a library and not the centre of everything without any layer above, we might be perfectly ok with it even now in 2023 for everything that's 100* simpler than GMail (which most of webapps are).
Honestly, my problems as a developer generally aren't with the frameworks (I'm mostly defending Vue here, as I find it predictable and easy) but with the build tools, which have gotten a bit out of hand and always feel brittle.