You seem to have asked about both high rep and high intensity? Obviously these two are at opposite ends of the spectrum so which one do you want to know about? Or you just wanting to compare and decide which is better?
As far as high intensity deadlifts go, I personally love them and think as far as powerlifting training goes they help me a ton. However obviously the closer you’re getting to your 1RM the less total reps you’re gonna get in and the more it might impact on your training, however I am still managing to pull heavy every week without it seeming to negatively effect the next weeks session, although I think some people have talked about the guys pulling big numbers not being able to deadlift heavy with as much frequency, but once again it all depends on your recovery and experience level.
I don’t have much experience with high rep deadlifts because personally I hate them, I do however do ‘high’ rep (10 reps) stiff legged defecit deadlifts as a way of trying to build up my lower back and hamstring muscles. My reasoning for this is that with high rep deadlifts my form will tend to go to shit and its one of those things that because you’re using a lighter weight your form will almost definitely be different to your form when using close to 1RM weight. Hence why I like to do heavy as fuck cluster style deadlifts as my actual deadlift training, because that’s going to emulate my form in a competition more closely.
Hope that makes sense and I kind of answered what you were asking?