Then, frankly, you are playing it wrong, because Sunbreaker has a rather sizable lead in average K/D over striker and defender, and over every other class since TTK came out. Whatever your perception might be, Sunbreaker is wrecking it in PvP comparatively speaking. Additionally, to your point, just because a counter exists does not make it as effective of a counter. I guarantee you the ratio of those counters he listed being effective against Sunbreaker is far smaller than the ratio of successfully executed counters against the other classes. That is why the Sunbreaker now has the best K/D in crucible in the game.