Your question was literally "Is Carter substantially better defensively than Kadeem Allen?" The answer to that is, by all indications, "yes". The post you initially responded to didn't advocate for the Celtics drafting him. Given Ainge's preference for length and athleticism, I'd be surprised if they do. He strong, smart, tough as hell and can knock down open shots, but not nearly as switchable as Smart. Derek Fisher is the comp that everyone seems to throw around for him. If they do draft him, Marcus should start looking for a real estate agent.
This is a general 2018 draft thread, I figured
@PaulinMyrBch was just making an observation about Carter, not necessarily recommending him for the Cs.