Will my overall posture be limited because of my maxilla?

I recently have become more interested in improving my overall body posture, and I learned that spinal posture has an effect on lower jaw position. Moving your head from a forward leaning position to the correct posture naturally moves your lower jaw forward relative to your upper jaw.

When I was a kid, I received orthodontic headgear to "correct" my overbite by moving my maxilla back, but I highly suspect that the overbite could've been fixed by correcting my spinal (and tongue) posture instead. When I stand up straight in the correct posture now as a young adult, my bottom incisors press against my top incisors, which will cause problems if it remains like that. This has been discouraging for me, and I'm kind of losing motivation to work out to fix my body posture. Do you have any recommendations for what I should do?