I removed a couple of the enchants just to reduce bloat in my modpack with Ensorcellation, and I can still find them in dungeons (dungeons generated after I disabled them) and dropped from Champions, who just drop loot based on book enchanting. Is there a way I can disable these from showing up in loot myself?

Im not sure actually. There certainly isnt right now. Once I update to 1.19, ill take a look at using feature flags for this.