The risk:reward just isn’t worth it for them and, realistically, they have much more important things to develop (core strength and control, hamstring & glute strength,
Either way, actively avoiding low back flexion in your training (as an elite lifter, not a general fitness enthusiast) isn’t doing you any favors.
And, in my opinion, you’re a lot less likely to hurt yourself (and a lot more likely to lift heavier weight) by strategically training your lower back in its weakest position.
Downloaded and read by nearly 10,000 lifters, The Deadlift Bible is my own creation complete with 4 instructional video tutorials and an entire manual outlining optimal deadlift technique, progressions, programming, and more.