Should be optional.

According to statistics, only 0.02% of the Internet still using IE 10. It means that IE 10 is less popular than IE 9 and even IE 8, but Normalize doesn't support them. In addition, Normalize.css is "a modern, HTML5-ready alternative to CSS resets", so it would be logical to get rid of redundant, rudimentary code.

Statistics taken from here

Would be great to create tool in which you could select which browser support are you interested in, and as the result you could download bundled CSS file with rules related only to the browsers that you've selected. Alternatively, maybe a CDN link, since there are finite number of combinations it is doable.

If someone could divide the rules based on what browser does they apply to, i could create bundler and web gui

For example, each rule could have comment specifying which browser requires them

sometag {
  rule-requred-by-firefox-only: value; /* required-by: ff */
  rule-required-by-internet-explorer: value; /* requred-by: ie8; ie9; ie10 */
}

EDIT:
From what i've seen, it's already done in a way. But this project hasn't seen a new commit in 2 years. Is anyone interested in such feature?

@kamilbeben I believe you are referring to something akin to browserlist and polyfill.io.

I compiled all these " junk" browsers myself (normalize-oldies.css) : it represents a small addition of 1kb and doesn't really hurt modern dev.

In any case, the project hasn't been maintained and updated for a while, which, by the way, makes it possible to reconsider the idea of "throwing out the old stuff" :-)