It's hard to deny that some of it is fun to listen to and see live (Evile is alright despite their blatant Slayer-isms), but I'm not really too hell-bent on wasting my time with a whole scene of completely derivative, throwback bands when Municipal Waste got it right on the first try. The ones that actually have something new to offer and aren't just pretending it's 1987 (maybe Rumpelstiltskin Grinder, for instance) are generally listenable, but there's such a significant drop in quality that it doesn't matter much.
Pure thrash metal is kind of an obsolete genre if you ask me. The only way to call your band thrash and create anything of value is if it's been mixed with a significant portion of other influences like black, death or grind (Bestial Mockery, Desaster, Ghoul).