In his absolute prime which was probably years before the Gvozdyk fight. I see him knocking out every light heavyweight in history.
He wouldn't beat these fighters IMO. Archie Moore Ezzard Charles Roy Jones Jr Michael Spinks Bob Foster These are the cream of the crop when it comes to H2H at Light Heavyweight. Some of the fighters below would also be close to 50/50 match ups with Beterbiev. Michael Moorer Gene Tunney Billy Conn Dwight Muhammad Qawi Sergey Kovalev Matthew Saad Muhammad I think it's possible Beterbiev is in the top 10 of all time in regards to H2H ability. But there is alot of tough match ups for him and Beterbiev's resume is good but not outstanding by any means. I also don't think Beterbiev beat Bivol once either and he was beaten quite clearly in their 2nd fight IMO.
I think he's the best we've ever seen at 175. I also believe that in a h2h sense a typical dominant champion of today is better than a typical dominant champion 50 years ago, though there can be exceptions. Bivol certainly lost the first fight and the second could've been a draw. Either way Biev was 40 and Bivol in his prime.
His prime was probably before he turned pro That said, his skill set got better after he became world champion He added alot of subtlties to his game later on which saw again Callum Smith and Bivol. I just hope he is juicing his nuts off and comes back fresh and as a monster whenever that may be