Take Marcus, Time Lord or Horford away, just one of them, and we are probably no longer number one on defense. That said, Marcus is clearly the defensive heart and soul, the undisputed defensive leader according to Time Lord, and the biggest drop is probably taking him away, although we are blessed to have White now in the event Smart is out for a short period.
Gobert tends to win this thing, but Utah is struggling some. I’d have said Dray is a contender again had GSW stayed right behind the Suns, but they are sinking. Kawhi was injured all year. This could be Marcus’ year, but I suspect Giannis will win it instead (superstar bias), especially if the Bucks close this year strongly.
Working strongly against Marcus is Bigs Bias: Only bigs have won it since Gary Payton in 1995-1996, and the only other guard to win it in the past 35 years is MJ in ‘87-88 (in the early years of the award, it was won by guards more frequently than bigs so Michael Cooper in ‘86-87, Alvin Robertson in ‘85-86, and Moncrief won the first two awards ever between ‘82-84).