[Cthulhu_]

It Depends, as always. The problem React was originally solving was that DOM updates cause re-rendering which can be slow; jquery (usually) works directly in the DOM, so applications heavy in updates don't perform well.

So initially an equivalent React and jQuery app would have React look a lot faster, due to smart / batched DOM updates. However, because React is so fast it made people create apps differently.

As always in software development, an application will grow to fill up available performance / memory. If people were to develop on intentionally constricted computers they would do things differently.

(IIRC, at Facebook they'll throttle the internet on some days to 3g speeds to force this exact thing. Tangentially related, at Netflix (iirc) they have Chaos Monkey which randomly shuts down servers and causes problems, so errors are a day to day thing instead of an exception they've not foreseen).