Hips are quite a tricky thing to understand because what people understand as 'hips' depends on where they 'feel' them. Articulations of the hips involve how the thigh bones, pelvic bones, and the sacrum all move relative to each other.
Tightness/difficulty in the hips is a result of holding patterns between these things (all permutations), which is always because of how you hold yourself up.
Freedom in the hips relies on each component part of this intricate set of joints being free to move in the way 'it prefers' without any particular part of it being left responsible for catching and holding your weight.
Here is a bit more of an explanation of what we are looking for... a taster for what I will be working with on this weekend's Saturday morning deep dive workshop on Zoom