Written by deadone on 17.01.2014 at 06:46
Thrash did evolve. It evolved into Death Metal (via Possessed, Kreator etc) and Groove Metal (via Sacred Reich, Exhorder etc) as well as Death Thrash (e.g. Nunslaughter's Goat album) and what was called Horror Thrash (basically cross between Thrash, Grindcore and Death Metal and a pinch of punk e.g. Ghoul and Frightmare)).
It also evolved into stuff like The Haunted, Witchery and Darkane that combined elements of Swedish Melodic Death Metal.
Definition of the Thrash Metal is pretty narrow though and arguably any movement outside its definition changes the style to something else.
Also arguably Megadeth's RIP and Metallica's Black album aren't really Thrash.
I'm quite late replying to this but haven't been on here in months! I was saying that thrash as a genre itself hasn't changed very much. It certainly did have major influence on those genres you mentioned, but they aren't thrash. For example, death metal has a quite a few different branches (technical, brutal, melodic, death and roll etc.). Thrash does have some bands that take the natural attributes of the genre and put their own spin on it, but I was merely noting that it occurs less in thrash than most other metal genres. Also the most popular new generation of thrash metal bands like Evile and Municipial Waste are really just doing the same as bands like Exodus and early Metallica, but worse. Whereas popular new age death metal bands like Amon Amarth and Behemoth sound very different to the genre's ancestors like Death or Morbid Angel.
I actually thought that Trivium's album 'Ascendancy' was one of the freshest sounding albums of the 21st century that could fall under the thrash umbrella. Another one I liked from a new band, though not sounding particularly original, was the band Essence's debt album.