No, they will not, ever solve that issue with respect to macro
nutrients, NPK, GH etc.
They can supply the traces to some degree in lower light tanks and
higher light tanks to a lesser degree.

There is a noticable improvement of flourite, EC, Onynx sand vs plain
sand.
But you can do well with either, just make sure you taske care of the
water column and things will go well.

Some will say you can add fert balls to the substrate but you forget,
plants show preference for the water column given a chocie between
substrate of water column in a number of controlled test.

That is also my observations for many years using both sand and water
column dosing methods without any sub strate fertilization and also the
reversed, nothing but substrate fertilization.

Onyx sand is worth it for me, it's a one time expense, certainly not
needed though.

Regards,
Tom Barr