You can pretend to understand what it takes to ban bots without catching humans in the crossfire. There is no magic “ban wave” button that Blizzard can hit every week. To do weekly banwaves would require hundreds of manhours each week just to scrutinize between bots and human grinders.
Your mind lives in this dimension where bots are so sophisticated that they outperform human reactions to dynamically changing environments, but are also so obvious that Blizzard can easily ban waves of them every week for an entire ladder season.