Smart man. Back in the day when there was money, fame and prestige in the sport, some were willing to take the risks for that. These days there is no money in it and very, very few people watch or care, so you have to ask what the point is? There are plenty of other motorsports that you can get your jollies from as a driver without so much risk. From drivers I have talked to that have raced irl cars, no one has ever found them much "fun" or challenging in a positive way.
Also he's already been in a back brace once, so he knows the possibilities.
My understanding is he comes from a moneyed background, so probably the family said it's time to knock it off and take up being involved in the family biz and you can still race sportscars or something.