Ryna Hart is generally one of the best players around.
It is true that in Tekken movement precision matters. for example, Top players always backdash with block (it's called backdash-cancel - if you only perform backdash, you're very vulnerable).
Top players are also about brilliant reflexes (they just see most moves), knowledge about the character's moves advantages and disadvantages and experience (when and how to stand from the ground, for example). Standing from the ground is extremely important and often missed in the early playing experience. I've seen a lot of okay players who were completely crushed by more experienced ones because they didn't know how to recover from the ground properly. Tekken punishes careless standing up, a lot.
Saikoro, welcome to YOT members team