Why is Soraka allowed to exist in her current state

I understand the desire for that niche healer class in league, but that type of gameplay is so disheartening to play against its unreal. As a support main I literally just don't even try to trade when I'm against a Soraka because I know any meaningful play will simply be negated by her super spammable heal. Her sole purpose is to negate any bad play by her teammates or, conversely, and good play by her opposition. If you make a good engagement and win a trade botlane, it simply doesn't matter, as she will immediatly heal the ADC to full in seconds. Saying "Focus the Soraka" is unrealistic in laning phase, as she can sit half a lane behind her adc and still be able to do her job. On top of that, and ADC would have to be braindead to not be able to capitalize on the enemy team focusing the support. If you cant burst her immediately you lose, end of story. I would even prefer the old Soraka to the current Soraka, because at least her heal had a meaningful cooldown instead of just being spammable. Now she's just a braindead healbot that only exists to fix her teammates mistakes. Not only is she frustrating to play against, her gameplay is utter garbage. Its an entire game of running around pressing your w while the enemy team tunnelvisions you, because if they dont they simply lose. Not only is this the opposite of fun, its annoying for the team fighting Soraka. Something needs to be done about her largely negative effect on any game she's in, be it balancing or even another rework.