I can't do a single Nordic Hamstring Curl

Are Nordics something that should be achievable for everyone? I am generally speaking, exceptionally fit (5:30 minute mile, 355lb squat, 28 dead hang pull-ups, 415lb deadlift, 255lb snatch, 185lb BW,). But when I try to perform a Nordic using a small padded tool made for this exact exercise, I can hardly get past 90 degrees and I just fall helplessly forward, and I certainly can't descend in a controlled manner and concentrically flex myself back up.

I am very surprised that I can't do any of these but some people can perform multiple reps. I follow all the Attia exercise advice and also do BJJ 4-5x per week, so I'm pretty comfortable with all manner of movement, but this one is just out of reach right now.