anyone is saying that the defense shouldn't be able to match the substitution. Just that the offense shouldn't be penalized for the defense intentionally doing their substitution as slowly as possible.
Great thing is that there is a super easy fix to the problem. Offense subs, now the defense subs..... While the defense subs and the ref is standing there over the ball not allowing the play to take place just stop the play clock (not the game clock). Easy peasy. Everyone wins.