Not a podiatry? Talk to your dentist.
No. Common causes of tongue thrust include allergies, enlarged tonsils/adenoids, thumb/finger sucking, or a tongue anchored to the floor of the mouth. Heredity, neurological and/or muscular problems may contribute. Have an ENT physician evaluate this and then move toward occupational/physical therapy resources if surgery is not for you.
Trisomy kids have large tongue and also have tongue thrust disorder. Would glossectomy be an appropriate treatment?
Partial yes. In some cases a partial glossectomy (removing part of the tongue) can be very helpful.