You're presuming Zain would not have been a 2017 medalist in a full wrestleback.
Maybe, maybe not, but we'll never know because the UWW system punished him for punishing his opponent.
With the system's incentives, Zain would've been better off rolling over and getting pinned in 10 sec -- then his opponent would've had something left in the tank. Again, we're talking about a world champ the following year, so it's not far fetched to believe he might have made the finals if Zain hadn't beaten him up.
This is so colossally stupid that only UWW would employ it.
Thought I'd chime in as went to the 2017 and 2018 Worlds with old teammates-- my personal favorite wrestling event and I highly recommend it. Well run, tons of amazing matches, can get your patriotism fix in a rowdy international environment but also converse with knowledgeable fans around the world, and also great opportunities to organically hangout with some legends of the sport and hear them hold court at the local watering holes.
Anyways, thinking about this topic, I'm not sure that Retherford/Batirov is the best example re: a need for full consolations. I don't think many people had Batirov (Dagestani competing for Bahrain) coming out with a medal in that bracket, particularly as he was 0-1 at the Olympics at 65kg and already few years into his 30's. In 2017 after beating Zain, he lost in the quarters and the Russian rep that beat him then lost in the semis to knock him out of the competition as well. 65KG is always just a brute of a weight class as there are so many wrestlers that size globally and the surrounding 61kg and 70kg aren't Olympic weights. Batirov did make the finals at 70kg last year where he ran out of gas to lose at the end to another Russain (that tends to happen when you hit age 34!), but like most non-Olympic weights, 70kg really didn't seem nearly as strong or deep as the 2017 or 2018 65kg brackets (particularly with Chamizo moving to 74kg and Green seeming to drop more and more headscratchers).
I do think, though, last year's 74kg weight, though, could have been a decent example to make a case for full or differently structured wrestlebacks (especially with what was a really bad seeding system last year): With Sidakov, Burroughs, and Chamizo all on the same side of the bracket, only 2 would be able to earn medals (22 year old Russian Sidakov beat both Burroughs and Chamizo en route to his first gold, and then the 5x world champ knocked out the 2x world champ before the medal rounds in repeche). This brings up another question- currently there are 2 bronze medals, but I suppose full wrestlebacks would resort in just one again?
If of interest, below's the Retherford/Batirov 2017 match-- good match and you can see how crafty Batirov is on his feet. A problem was Zain giving up a reversal from top (not very common in FS) with 2 min to go when he tried to throw in the boots and power half-- that point would end up being a difference maker. When I watched this match again, I actually got the impression that Zain was a little tentative overall compared to his typical self (and particularly in comparison to, say, that slugfest in the world team finals that year with Molinaro). I think Batirov got to the legs a little too often and easily and even when he didn't score, he chewed up a lot of time on Zain's legs prior to stalemates. Just my 2 cents as enjoyed both 2017 and 2018 tournaments.