I'd have to agree with most everything in your post with the exception of, "
Deadlifts are one of those exercises where some people that aren't actually that strong overall can potentially use a lot of weight on. It's also not a great muscle builder." At least with a caveat. Conventional deadlift is a great muscle builder and can develop great overall strength by involving nearly every major muscle group. Competitive powerlifting however, is doing a disservice to the spirit of strength sports and ultimately the lifting community in general. The USAPL had to change the bench rules because some lifters were able to perform a ridiculous back arch with a wide grip. They were able to perform record breaking presses with the bar moving all of 4-5 inches. It's sad to say, they are going to need to address the deadlift next. Sumo deadlifts are for those lifters with strong legs in comparison to a weaker back. If the lifter has good flexibility and a long wing span, they can "lift" extraordinarily heavy weights with the bar maybe moving 5 inches. The spine is almost totally erect when they start the lift and requires very little extension to complete. I coach a couple 700 lb. sumo deadlifters. In the off season I make them train conventional. These same lifters struggle with 500 lbs. By the time in season training comes, they're more muscular and strong and as they switch back to sumo, their numbers increase.
Lastly, I think it's dangerous to not train deadlift. Training around the back or isolating the various back muscles in different lifts is no substitute. I can see NOT squatting heavy weight from a practical standpoint. Squatting with heavy weight compressing the spine is not necessarily natural. In life we push, we pull, and we bend over and pick things up. One can choose not to train the deadlift but sooner or later life may call upon you to deadlift. Be it bending over and picking up the end of a couch, dresser, piano. Maybe picking up your gutted deer to hoist into the truck. Maybe to bend over and pick up your unconscious neighbor to carry them out of the burning house. Bending over a picking things up is a natural human movement and as soon as we stop or avoid doing it, the more difficult it will be to do it later and in old age. BTW, I'm with you that they can be hard to recover from. I personally train it every 7-10 days. I only occasionally go above 90% and usually stop with 1 or 2 reps still in me. I believe this still gives a great hormonal response and keeps the grooves greased. It's also a great grip and forearm strengthener.
https://www.washingtonpost.com/wellness/2023/01/18/grip-strength-muscles-aging/