I don't think this is necessarily a bad thing.
From my own experience, I was very tense in my jaws, maybe because of bad bite and maybe because of bruxism etc. Before I started investigating my bite, I remember I had low mobility. Had a hard time forcing my lower jaw forward etc.
Since then I've had botox injections in the muscles controlling my jaw movements, to make them relax, and also started my orthodontic treatment.
I haven't had jaw surgery, but with the above I now have much more mobility in my jaws. Before I couldn't force my lower jaw forward to nearly as much underbite as I can now. It was a real struggle, probably a combination of having tense muscles, but maybe also something with the jaw joints.
Any way, my point is that maybe you're now in a more relaxed jaw posture and orthognatic position, allowing more normal degree of freedome?
But as always, I don't know what you're actually describing, it depends on the magnitude of the movement and what problem it's causing.