Hi, I've asked before but never gotten an official answer, but can Shredding Vibrato be played as a block even if you haven't discared 2 attacks from your card pool? If that's the case, why even have a block on it?

Similar to Neo Raging Storm, yes, it includes playing it as a block.

The block mod is there for a few reasons, but most visibly prevailant is cards like The Ultimate Team and Cassie which you either reveal or discard a card and it references the block mod.