Most of my spiders wobble, a few don't.
Some of my womas wobble too, some don't.
I don't worry about it overly much, as it seems to come and go with age and stress in many cases. A woma female with no wobble who was fully mature, developed one after a move.
Whatever causes the spider-webbing pattern which both spider and woma share, it must also cause this neurological or inner ear issue.
No big deal--it doesn't appear to cause them any distress. Real impairment from it is pretty rare.