Meh, I think this is just a convenient out. I’m not saying that there is no risk, but the other serious health risks was always a factor for everyone (so barring agoraphobia, not a thing) and covid is also less of an issue if you are up to date with your booster.
If he wants he can also wear a mask I guess (travel is all done private, so hardly any risks there. Or at least a lot less than for mere mortals).
Keep in mind he is a billionaire with one goal, protect his empire, and everything is allowed in that game… Even using legitimate concerns for some to get out from under being deposed on the stand.