I care, because it's a waste of resources, I care because I don't need a daemon written in JS running in a loop sucking up my laptop battery, I care because I like it when my software doesn't randomly get in a loop maxing out a core, I care because I like it when my software is able to push out 60FPS animations.
You know, things Electron doesn't provide.
I get it, HTML+CSS is probably the fastest thing we have for UIs today, and it's not half bad. That doesn't stop software from being absolute crap.