So what's the point in picking Kayle?

In what scenario is she actually good, with riot pushing the tank meta back into the game, what's the point in picking her? She deals less damage than an adc , she can't kill a tank, she can maybe kill an assassin, assuming they are bad, she can't get to the back line, even though she can kill mages, she can't get to them, she can kill the enemy adc, assuming she can get to her. If the enemy has a tank, you can't do any damage, the best you can do is ulting a fed teammate and hoping that it was enough, again assuming that you aren't forced to waste it on yourself. Like she can kill squishy targets, but so can assassins, the only difference is that assassins have access to the back line while she hasn't. The damage you deal to tanks(with nashors,rageblade, gunblade) is lower than the damage that your adc deals to them.