You misunderstand the function of block in this game. You cannot block people from playing against you in pvp. You can block them from sending you messages and joining your fireteam I believe. Can you imagine if blocking from mm was possible? You would block everyone better than you or you would get blocked in crucible until there was nobody left to play with.

After reading this post, I’m not sure the player you blocked was the toxic one.

Hmm I couldn't see people exploiting that at all.. and blocking every good player that beats them...til they just have a pool of plebs to stomp