There is nothing wrong with the rule in regards to this specific situation.
Right now the rules allow McBeth to ask the spotter to move his belongings.The spotter was there, and to my knowledge offered to move it, if allowed.
I think the rule should be worded to allow the belongings to be moved, regardless of the owners presence, but that would not have changed things here.
Because they were discussing whether it was a permanent part of the course - and that McBeth apparently moved a little to fast before getting a final ruling (though he might have thought it was final). The latter part I would still like to hear McBeths version of. They might have come to the right conclusion had he waited. (again, if he indeed moved to fast)
I cannot quite understand why they would need a discussion that long about making such a call. The spotter puts a random object at a random spot. Of course it is not part of the course. (the spotter should of course be allowed to have it there, to sit down during the day.)
So the problem was not so much with the rules, but with the officiating of them.
As for the proposed change: Where would you put a spotters chair on a hole with no OB?