The 70s seem to be highly rated simply because it was an era that Ali competed in. But do they really live up to the hype under closer inspection? An aging Patterson beat Bonavena and was arguably robbed against Quarry and Ellis. Gassiev would probably beat many of the 70s heavyweights let alone Usyk. The top 70s heavies are also totally untested against skilled super heavyweights whom they didn't have to deal with but whom the division is now filled with. I think the current era is likely the strongest era talent wise. If we say an era is 8 years than 2014 to 2022 would probably be a match for any prior era.