jQuery is just a framework, if even that. If you choose to use it to store state in html elements, that is your choice. And yes, a common one. But the framework does not force it. If you make an AJAX call in jQuery, you get JSON back. (Or, I use it to get JSON back... you can send whatever you want back.) You can do whatever you want with that JSON.
Frequently, I do store metadata in a DOM element because the next event I will react to is a click on that DOM element, so I already have a handle on it from the ui element jQuery gives me... I do not have to traverse the DOM. But if the future use of the data is NOT going to be a response to a click on a specific DOM element, then no, I will do something else with the data.
Again, just because everyone else does it doesn't mean you have to, and doesn't mean it is inherent in the tools. I'm not saying jQuery is the best tool out there... I'm saying that complexity in an SPA doesn't come from jQuery itself, but from design choices made with it.
True, it would be better to say that it's not great to build an SPA with just jquery. It compliments a number of other frameworks that are good for SPA's.
Frequently, I do store metadata in a DOM element because the next event I will react to is a click on that DOM element, so I already have a handle on it from the ui element jQuery gives me... I do not have to traverse the DOM. But if the future use of the data is NOT going to be a response to a click on a specific DOM element, then no, I will do something else with the data.
Again, just because everyone else does it doesn't mean you have to, and doesn't mean it is inherent in the tools. I'm not saying jQuery is the best tool out there... I'm saying that complexity in an SPA doesn't come from jQuery itself, but from design choices made with it.