Yea. You do have tight hip flexors! I think that time logged is the single bggest factor there, but if you can find someone to perform some active release or similar massage on the hip flexors you may be able to speed things up, but more than anything else just slowly spending time learning to relax the hip flexors as you stretch them will help a lot. The time can't be replaced.
The primitive squat is good, but that won't address the hip flexor issues. I don't have time to get into that now, but I will work on that.