Surely the greater difference would be felt by monitoring the usage in training. If some players do an hour a week (e.g. defenders at professional clubs) it will constitute a far greater fraction of heading than game situations over a season.
Next it’ll be knees and back injuries which could mean you’ll end up in a wheel chair — game will be become subbuteo for real. On the subject of head injury maybe we can just wear some sort of head brace which will absorb the impact of heading. There’s plenty of technology out there which will give the players what they need to head the ball without feeling compromised— to do away with heading imo will probably increase other forms of injuries.