I suspect that the low scripting CPU time on jQuery sites is because it's quite common that it's just being used for a few things (and even nothing at all), while the other frameworks are likely doing a whole lot more.
Something like JS LoC excluding the framework itself might give a better picture of it.
Using jQuery is definitely a different style of development than using something like Angular/Vue/React. I tried to clarify in the post (under "The Big Picture") that the data shouldn't be construed as me saying "React is slower than Vue or jQuery" but rather that there are characteristics of the way we build when we use React (combo of ecosystem, documentation, technical approach, etc) that leads to a lot more work happening on the device. The question is whether that's something that we're ok with.
Hopefully that came across in the post! I certainly don't want anyone thinking this is like a benchmark or anything that is pitting jQuery execution versus React execution or similar.
Something like JS LoC excluding the framework itself might give a better picture of it.