I have no problem seeing it displayed as it is, and like we all know, the seller also seems to know by his lower asking price, that it's not a top dollar, soup to nuts resto, demanding all the money.
Like was mentioned, people along the way could have left it as a nostalgic race car, which there are plenty out there, or during it's life it could have been rotisserie restored, finding every single date correct, part number correct, hose clamps to engine block and heads, and where even though it wouldn't have demanded the complete numbers match price, it would be worth quite a bit more.
But,......not everyone who comes across one of these rare cars, has the money, time, or recourses to do that kind of restoration. Owning a piece of history like a limited production, documented, COPO Camaro, is an awesome accomplishment, and the fact it's on the road and not been crushed at a salvage yard 40 or 50 years ago, is a great thing in my opinion,...original drive train or not.