It's not about junior vs senior. it's about hiring a competent developer. There are competent junior developers and there's plenty of useless seniors. Besides these, what you are building matters. If you are not dealing with hard tech, then a junior with a model could level up fast. If you are building complex hard tech then experience matters a lot for judgement, however some juniors could still keep up. The bar is at an all time high, but for everyone, seniors as well.