Nylium doesn't drop itself when mined with a non-Silk Touch pickaxe

If you break nylium with a pickaxe it will drop netherrack. You only get nylium if you break it down with silk touch.

Steps to Reproduce:

1. Obtain a pickaxe and nylium.
2. Place the nylium.
3. Mine the nylium using the pickaxe.

Observed Results:
Netherrack is dropped.

Expected Results:
Nylium should drop itself when mined with a non-Silk Touch pickaxe.