Nerfing someone has does more than just making them weaker
If you nerf all the lane bullies then the weak lanes and hard scalers will rise. Imagine if the fighter/bruiser meta came back to top lane and everyone but Jax got their early game nerfed. Jax would have a huge spike in popularity despite never being touched because everyone who bullied him before got nerfed.. This is what happened in the ADC role and with Vayne. Vayne has had a huge spike in popularity recently. Not because she had a big buff but instead everyone who could really bully her got nerfed.