JamesBond007, a GOG user, detailed in another thread
the soundbanks they found to be missing. Though none of those are ones I miss all that much (maybe Kamikaze, but I'm happy just as long as they give me Angry Scotts and Thespian), it is, indeed, a shame that a Remastered version of a game actually manages to take something out of the original, instead of adding... hopefully they'll find a solution for this, although the problems leading to it may have something to do with the original files having been lost, or some sort of obscure copyright issue; anything's possible.
There are also noticeably some flags missing, other than the soundbanks, which is also sad, because they took out most of the non-national flags and some of us don't particularly enjoy turning Worms games into actual international squirmishes amongst teams representing countries.
I wonder whether some of the soundbanks were actually removed because of the whole politically-correct "our edgy ethics above everything else" society we live in, and that left Team 17 afraid of hurting the feelings of some annoying vocal minorities...