I'm not talking about commercial boats.
And I agree that 6' wake is almost impossible for anything other than a large ship.
But 3'-4' isn't.
I can make 3-4' wakes with any boat I own. Hold the throttle just right taking off, short of plane, just ride it like that, the wake close to me will be that height. I don't do that to other boats, but it's possible. I don't have a boat on which I can make that size wake at 30 knots. You'd have to be plowing to make it. That's why I suggested it might be possible that the wake that caused the problem was actually made as the SF first accelerated to go around him and was close at the time.