This is the kind of thing you should implement in a JS library, or by preprocessing the image before you upload it to the web site, not add to the browser platform spec.

I was half-joking, and primarily meant to point out that the pixelated versions aren’t how those icons looked like to users back in the day either.

But also, for faithful CRT rendering you want to take the actual screen pixels into account, possibly even the subpixel layout, very much like for text rendering. Therefore there’s something to be said for that to be a browser-level feature.