In my opinion, tackling fundamentals have taken a big hit over the years as teams held more practices in helmets and shoulder pads only. I only played high school football, and it was back when helmets-and-shoulder-pads-only practices were rare. But nevertheless - I hated them. You were still expected to close on the ball carrier and wrap him up, but obviously you didn't want to hit your teammates around the hips or thighs when they had no protection, So, you had to go high on them. I think now that full-pads practices are fewer and fewer, this becomes a bad habit that carries over to games.
I get the good intentions of moving away from full-pads practices, but it may have had unintended consequences. So I like this idea of no-pads-or-helmets tackling drills, because at least there's no natural inclination to go high on the ball carrier.