I could talk for hours about what nu-metal actually means. I hate talking about music genre classification normally, as it's just a clever way for rich dudes to sell something from Band B that sounds like Band A to fans of Band A.
Also, music nerds get really passionate about it. Gloating about the most obscure genre names. Second New Wave Of American British Heavy Black Metalcore. Fuck off. Class music is class music.
BUT.
Nu-metal is a really interesting one, as it basically covers that point in the 1990s where metal exploded in a load of different directions at once. The most basic definition of nu-metal (to me) is basically a combination of rap, electronics and metal. The broadest definition would also include Roots by Sepultura, Coal Chamber, maybe some Fear Factory. Faith No More. Limp Bizkit and Korn. But none of that sounds anything like any of the rest of it.
What people call thrash metal, death metal, black metal, in their broadest terms they have certain defining sonic characteristics.
But what people call nu-metal, and dismiss nu-metal for being, is nebulous.
There's an element of snobbery to it, and young fans have inherited prejudices about it from the generation beforehand. It's much cooler to love Slayer than it is to love Korn, but fuck it, there's plenty about Korn to love.
Nu-metal just never had the stick-around credibility of the metal classics. There are albums that have come out since that would constitute required listening for new metallers - Leviathan, for example - but I don't think there's anything from that period, from that GENRE, that people would insist is essential in the same way they would say you HAVE to listen to Vol. 4, you HAVE to listen to Master of Puppets. Am I forgetting something? Probably?
But I like an awful lot of it and without any reservation or caveat at all.