I think the Jackie Stewart does have a point, but only so far. The GPDA has done an immense amount of work towards the safety of F1 and Lewis is reaping that work for no input back. I think he should be able to find a few hours for them. It would be good for the sport and a good example to the next generation. If the busiest man in F1 in the form of MS could find time, then Lewis should also be able too.
As for JS saying that no one did more commercial appearances than he did, he does have a point. Jackie Stewart, Barry Scheene , Henry cooper, they where the pioneers of being walking bill boards. If you see interviews with any of these three, the one thing that they all say is that being on the road for commercial appearances was the highest stress point of everything they did. Todays F1 prima donna's turn up to photo shoot that has already been prepared, stand on the X, smile, look moody etc a couple of flashes and then it is off to the next. Stewart and co would be there from the start to the finish, waiting for  the development of the perfect picture, no digital back then and then off to the next etc. He does have a point with what he says. It is just that very often, he does not put it across well.

Matt