i think that in order to get into the deep squat, you must be able to get your knee past your toes in the kneeling ankle DF exercise or propped up on a stool, relatively unloaded.  the more the better, without your heel coming up.  if you can’t, this indicates a bunch of restrictions that the body will have to deal with as you try to attain the bottom position. some restriction may be in the ankle itself, but it may also be the symptom of many other restrictions both up and down stream. any/all of those restrictions will more than likely hinder your deep squat. like the deep squat, i think you can think of the ankle DF as a test also.

that doesn’t mean you can’t squat (the exercise) at all. most people say a good enough squat is just to horizontal quads or just below.  doing heavy squats down to the very bottom every time is a demanding movement in many aspects. worthy goal though.

re: banded distractions and smashes

i think they are not necessarily better than one another. both have their role.  sometimes restrictions are dealt with via distractions, and some need more work like smashing in order to make a mob work better. depending on your situation, you may need some smashing to help get rid of restrictions so mobs do their job. mobs can also reveal where you should smash as well, as you find corners you can analyze those corners and smash appropriately. corner work is a form of restriction removal – oscillation and bending the paper clip, etc.