Gee gollies, shouldn't this thread be over on the "Training Q & A" forum?
Anyway, no I don't think deadlifts (dl/dls) are overrated! As a matter-of-fact, IMO the diamond, or hex-bar, dl is arguably the safest and best single muscle mass-building compound exercise in existence!?
The diamond bar allows you to start the dl in a very low top-of-thighs-parallel-to-floor (or even below parallel!) position, and allows you to pull the bar straight-up and back over your heels (a so much safer "bar path" than the straight-bar dl)!! Why, you can even finish off each rep., in the diamond-bar dl, with an effective shrug!
The diamond bar dl actually allows you to combine practically ALL the benefits of BOTH the straight-bar back squat AND the straight-bar dl movements into a SINGLE highly-effective mass-building compound movement (e.g. arguably better than even the breathing back squat for say high reps)!?
The big danger (of course!) with the straight-bar dl is that one has to invariably round their low back with heavy weights, to a greater extent, when clearing their knees. As we all should know, legions-upon-legions of weight-trainers have injured their lower backs attemping PR dls, or struggling to complete those "last few reps."!!
Sure, we all know we should all keep our backs "flat" when we dl, however most of us "slip-up" and round our back for those last few reps., or that PR attempt! And when we do (or when we set the bar down!), we feel that "uhh-oh!" twinge of pain in our lower back!
Of course, some trainees have "low backs of iron" and never experience lower back problems doing straight-bar dls! But sadly, most of us find out the hard way (!) that we are not a member of the "low-backs-of-iron" fraternity!!
All I'm saying is that the diamond-bar dl arguably works the muscles of the thighs, glutes, hips, lower back, and traps, more thoroughly (and much more safely!) than either the straight-bar back squat or the straight-bar dl!? In high-reps., the diamond-bar dl is a great muscle mass, and stamina, builder!!
The diamond-bar dl is certainly a candidate for the title "greatest single compound exercise"...surpassing even the sacrosanct back squat!? This is because it concurrently works more large muscle groups, and provides greater low back and knee protection, than does the barbell back squat!