Its a game with a very long learning curve. And even when you master it, you are not going to absolutely destroy everything, staying very dependent on team. If you have friends who also mastered it, and you team up, then yeah, its hella lot of a fun.
Just to add on grinding: I disagree about the need for grind, because playing on tier 10 is not superior to playing on tier 5. It's just more advanced, and just different kind of gameplay and techniques. Many people once they get to tier 10 get disappointed they didn't become gods, and go back to tanks they enjoy on tier 8 or 5 or 6 whatever.