Only affects caves, ores generate fine in surface biomes.
Tested with Terralith (mod version) and Cavernous (bare bones version).

Edit : I did some more testing and found that Cavernous was actually the sole culprit (and was overriding Terralith's caves. I thought they may have been missing a tag that may have made the mod not recognize them as overworld biomes but I couldn't find anything with my limited understanding of modding Minecraft. Ores from other mods generate just fine.

Looking into this datapack I can imagine why the ores aren't generating - Their biomes aren't in any of the relevant biome tags. I use convention tags for this, as noted here in the FAQ: https://wiki.mythicmetals.com/faq/#related-biome-tags-technical-stuff

This is not something I can really fix directly. I suggest contacting the datapack dev and ask for them to add their biomes to the relevant tags so that modded ores/features are respected