Most old-time gamblers are good at controlling and faking their emotion I don't think it will be an issue at all it's the newbies that will have a hard time proving if they can take a loss, because while you are learning how to gamble you'll also become good at concealing your real emotion
so it will be no problem for old gamblers.
I agree, the more experience you have with gambling the better you can handle your emotions. I have been gambling for a long time in physical casinos but only with a small bankroll, I got used to having bad beats where the luck just runs against you. It's always great to gamble in a biggger group so you see all kind of reactions.
In the end these kind of protections are mostly for the new gamblers, I think the chances of becoming hooked on gambling is especially high when you are new to all the games.
Eventually he can handled it, he can be used to it, he needed to know that in gambling there is always a higher risk that is needed to take, we can never always win in every game that we put our money, there will be times that we will lose the amount we invest sometimes, and maybe sometimes a lose streak will come, but we need to learn and endure the every setbacks in our game, have your emotion be stable as always.