Taylor is not a decent hitter, he hasn't been above average per OPS since 2017, is sub .300 OBP in the past 4 years - even now, in what is a above average season for him (compared to the past 5 years), he has a pitiful .258 OBP. He's a mediocre hitter who is a plus defender in the outfield.
Lewis sitting frequently is probably a plan from the whole collaboration, not just Rocco. Just like Buxton. You can fire Rocco and pretend like that will be the main factor to improving the team, but this front office will just replace him with someone who fits their vision. Resting players incessantly and over-platooning isn't going to come to a total halt without him.