If we are going to call this a sport, then we should allow coaching just like other professional sports allow. But I think it should come from a single pre-designated person, like a friend, teammate, spouse, etc. We can't have four people yelling out different things causing confusion.
For experienced shooters, unless the stage RO is a personal friend and agrees to coach, I don't think ROs should in any way be obligated to coach all shooters. I've been an RO, and that would be a nightmare.
For newbies, I absolutely believe that the ROs should be allowed to coach if the shooter requests it. There's a decent chance a newbie has a newbie friend, and we don't want the blind leading the blind. We need to create a safe and fun environment for new shooters, and giving them help, guidance, and support is a key way to get them coming back for more.
My 2c!