As the title says, I tried it on both an already enchanted netherite pickaxe and a normal diamond pickaxe, but neither of them put broken blocks into my inventory.

Yes, I just unlocked the spectrum enchanting yesterday and was trying out this new enchantment when I found this out

That is the enchant that is removed yes. Do you have the requisite Spectrum progression to use the Inventory Insertion enchant?
Also Charm only causes issues for <v1.2.0 worlds updated to 1.2.0+ otherwise it has no issue.

Works with Spectrum alone. If anyone can tell me the mod it collides with I can get it fixed

Charm would be my only guess, as they have a similar enchant. I will test it out later.
But I aslo have that enchant disabled in the Charm config, as it was known to cause other peoples drops to be inserted into the player with the enchants inventory...

I have already disabled charm because I've heard that it affects performance, enchancement also had a similar enchantment called "collection" and got removed, it is because of this?