I think there generally a safer exercise (especially with a trap bar). No need for spotters. Part of the thesis is that the deadlift is a better tool for knee rehab due to the ease of coaching and that the majority of force is born through the ankle.
They can murder your back though, if you don’t get your form down.
Yeah, take the studies with a pinch of salt.
Sumos show larger quad activity over conventional deads from 13 collegiate football players.