Have you seen how many messages you can pump through and transform on a node process? Yes, there is an abstraction and that's a cost, but v8 perfomance is "good enough" for almost everything.

Maybe not a coin miner or a graphics engine; but cpu is never really the constraint for applications such as those inside electron containers. Where you see them chewing 100% of a core, those are bugs.

Also, while th e language has flaws modern; JS vms are pretty bleeding edge....