Unless the rules have changed, coaching while the players are on the pitch isn't allowed in Rugby Union. (iirc, same for cricket)
It is in training sessions. F1 drivers' training is limited to whatever they can manage in testing, of which there is hardly any, and at events. And even then, most of the running in free practice sessions at events is aimed either at evaluating or validating upgrades or setting the car up for the race. Runs where the driver is free to concentrate purely on practicing his own skills and experimenting with different lines and driving techniques are very rare, since you don't want to be playing around with that sort of stuff too much if you're back-to-backing two front wings, because you don't want to introduce unnecessary variables.
Giving advice on technique while the player is on the pitch is permitted in association football even if not in rugby, but such advice is never given during matches for the same reason you don't hear drivers being given driving tips during their Q3 runs - it's not helpful. But in my view it's perfectly natural for such coaching to occur in free practice, just as it would for a footballer in a training session. If it's still happening in races, that in my view is just an indication of the lack of training opportunities in F1, because merely by talking to your driver you run the risk of diluting his concentration and costing yourself time, so if there are still big enough gains to be had from coaching even by race day to make it worthwhile to bother a guy when he's busy driving says more about how hard the cars are to drive and how wise it is to not let sportsmen train between events than anything else, in my view.