There is always a risk of a pitching fatigue death spiral, no matter how many innings you draft. Once you get past a certain threshold the probability of it gets very close to zero, but it is still possible to have every game be 20+ innings. Obviously the probability of this is extremely low, but it is not zero.
When you get below 1300 (assuming you don't have restrictions like super low cap, everyone in Petco, etc.), the probability starts getting a lot higher than zero. You're a few early extra inning marathons or ace shellackings away from serious trouble. You might be able to navigate your way out of it eventually by running mop-ups into the ground, but if the mop-up starts the game below 90% or so then you run the risk of an early injury and the spiral getting out of control quickly.
Seems to me like people are way too willing to play with fire. Is the slight improvement in quality of your pitchers worth even a 10% chance of finishing near the bottom of the tournament? I would say not even close, especially since the owners who have dominated this tournament in recent years have never in my experience flirted with super short innings. Not to mention, for this $70m in particular, one of the things fatigued pitchers start doing is giving up home runs at a much higher rate than usual, and that percent multiplier is gonna hurt a lot more in the super HR friendly modern era. Time will tell but I personally think it's a terrible idea.