Not levelling up undoubtedly the best PVE subclass starting 25 Levels and 280+ Light ago shows inexperience and that's probably why you were kicked. Being a Striker Titan means you have to get close to your enemies to use it, risking your life which you probably would have done when it was charged because of temptation. You were probably replaced with a Nightstalker or a self resurrecting Warlock which does have use in the Raid, particularly Hard Mode.