I think I get the overall idea, but why are we encouraged to write <x-slider> instead of <input type="range">? I know that most of JS ninjas go bezerk at the me

I think I get the overall idea, but why are we encouraged to write <x-slider> instead of <input type="range">? I know that most of JS ninjas go bezerk at the mere mention of progressive enhancement these days, but in this case it seems the most sensible thing to do, regardless of ideological affiliation. We already have a standard element that is supposed to render a slider, why not just use it and add things to it?