Heeeey...I mean, let's be honest, The Book of Vile Darkness is a terrible supplement even if you ignore all of the extremely atrocious and objectionable narrative content contained within. Like... just the game design stuff is bad. It makes a worthwhile museum piece, perhaps a polemic on how to absolutely not introduce mature themes into your tabletop RPG, but I struggle to see what value it could possibly hold otherwise.
I love the Crushing Fist of Spite! And the additional Demons, Devils, and Undead are useful, too. Apocalypse from the Sky makes for a good "Big Evil Ritual you have to Stop" in a populated area. And the Darklight spell is just -mint- for Underdark adventures.
I'll definitely agree most of the content is trash, but there's some shining embers among the ashes. Though you definitely have to wash a lot of the grossness off of anything you take from it, in the end.