Polished Blackstone Bricks are crafted from Polished Blackstone.
Deepslate Bricks are crafted from Polished Deepslate.

So either Deepslate Bricks should be renamed to "Polished Deepslate Bricks" or Polished Blackstone Bricks should be renamed to "Blackstone Bricks". This is a duplicate of the following:

MC-218826
MC-223901
MC-224608

But all are marked as "resolved" which I believe to be incorrect. This seems to be a leftover from when Deepslate Bricks were not crafted with Polished Deepslate and the name wasn't changed to coincide with the recipe change