Do hypothetical 1000% performance gains matter if perceived performance is already within acceptable limits?
Wasting time gold plating solutions with no meaningful tradeoff is a negative trait, not a positive one.
For an individual, no.
For the gigawatt of power you just wasted nationwide, yes.
Electron does not have to be slow, just how web applications in general do not have to be slow, multi-megabyte monstrosities.
I bet you would be surprised if you knew where even specialized, sort-of-embedded UI is moving. Hint: it’s not native.
Qt?