For 2 fairly intelligent guys you do not listen very well.
There are 100's of thousands of dealers of 1000's of categories shopping ebay for inventory. It doesn't matter if it's guitars, vintage clothes, comic books, toys, cars, every category you can imagine there are several dealers of it shopping ebay for the best material with good margins. If you think George Gruhn isn't shopping ebay you would be foolish. If you think Peter Klutt and Shaughnessy aren't shopping Ferrari's on ebay, now you're getting into the dumb stages. Hell he found this chassis on ebay!!
$2.8M Ferrari Chassis Found
Yes, if I was still young and hungry I would definitely still have 50 used guitars for sale at all times, but I'm not. I'm very selective with what I buy and how much margin there has to be, because the fact with used guitars is, as you all KNOW, you're depending on correct descriptions from the seller to judge all the above, used guitars are usually old guitars, and old guitars are typically fairly dirty, have old guitars problems, and probably had enough old guitar problems that's the reason they're for sale, it's somebody elses headache. There are just as many old guitars that are in good technical nick, but the difference between the 2 is more luck than amount of time talking to the seller. After 20 years I can pretty much just read an add and tell if the seller has even inspected the guitar before listing it. Take the current add for the metal design, you're both aware of, and read the add "yes it needs some tlc", well WTF does that really tell me except he can't be bothered to actually tell me what he knows it needs, and I have to chase him down and play 50 questions to find out. That's an instant PASS and back button, unless, it's something very desirable and worth the effort. LISTING a used guitar for sale the right way, takes alot of time, prepping a sold used guitar, the right way, takes alot of time. The MARGINS on used guitars are far better, but it's offset by a much higher workload. Which is generally why I just buy lots of seconds that I just have to pick off a sheet, far easier.
Roman, for all his faults, knew 1 thing you guys ignore. There are many tiers of pricing, and absolutely, nobody was higher than Roman on more contemporary material, but he also knew, the top tier buyer, wasn't spending his time shopping on ebay. He's spending his time MAKING MONEY!.Then when he wants to scratch the acquisition itch he has a reputable dealer [or network of them] that he shops and buys from, because the last thing he has time for is to constantly shop what's passing over ebay for that rare nut that almost never appears.
80's/90's RG550's are a dime a dozen, so are R's and S's, etc. No, there's still some margin left is plenty of them but it's not enough for most dealers to play with, those are for very hungry dealers. I'm looking for big cats, and so is every other good dealer in every category.
The end result of any open auction is pitting who is searching for, found, was interested in enough to track, and bid, on any given item during any given 1 week period. Yes, sometimes the big boys will pop on ebay and have a look, which is why you'll see EVO's listed at $14,500, or JS2PRM's at $14,000. This is top tier pricing with a hair of crazy thrown in. They're trying to hook those big fish if they happen to swing by. And every now and then, they will, and put one in the boat. But that's generally not the case. The typical sales results are average buyers willing to pay average prices, and are searching hard and spending lots of time to do so. [some, being more average than the rest].
Bottom line, ebay is an auction and thus is still a wholesale marketplace, where 2 privates can get together and create top tier pricing, but more often than not, you end up with typical results for a wholesale marketplace.