I'm not saying he wouldn't still beat Lemieux. I think he's a favourite over any active MW today. Even though he isn't the same style of fighter he once was, he's still a very good fighter and in my opinion he's still the best MW in the world.
I agree he's still close enough to his best in 2021. Id agree he's still beat a guy like Limieux as well. .Its the elite guys like Canelo he struggles with
It's a bit like how Hopkins clearly wasn't prime when he was 40, but he was still an extremely good fighter who had to adjust his style to stay at the top of the sport.
Tbf I didn't really think he struggled with Canelo. But that's semantics, he clearly capable of performing how he did against Canelo and that shows to me he's still capable of performing at the highest level.
His power is not based off speed and reflexes but balance and timing so as long as his knees dont give out he will remain dangerous.
What does prime even mean? Golovkin isn't capable of performing the way he did in 2014. He is capable of beating the level of fighters he did in 2014. He has a better jab than he had in 2014. He isn't physically as capable as he was in 2014. But as for your specific comparison, it's really difficult to say with Hopkins. He didn't fight Tito the way he fought Johnson for instance, and after that it was 3 years until he fought a decent opponent and that was an under sized Hoya. I mean you could argue the next decent MW he fought after Tito (who was himself undersized) was Taylor, so a decline can be masked. But then again Hopkins looked awesome against Tarver, Pavlik, Cloud and Pascal. Some fighters it's obvious when their prime ends as that's when they aren't able to compete at the same level any more. Others are able to compete at the same level even when they have declined, because they adjust their style to compensate.
Prime GGG, 2013-14, works Canelo. GGG should have got the nod the first time, second I give to him but it was closer for sure. 2020 Canelo is some fighter, P4P no.1, he wins for sure now if they did fight. Always pulling for GGG though.
In 2014 he fought Rubio , Geale and Adama.. He still beat those guys . . There's polls that have him the heavy favorite over Andrande and Charlo right now !! Prime in relation to GGG is an excuse fanboys make to justify his struggle and loss to Canleo. Many guys were still prime and peak at 35. Prime is a simple concept. Wear and tear , mileage and discipline. You turn up in poor shape you can loose your prime over night. GGG had very little wear and tear on him and live a clean healthy life style.
I said I'd favour him over anyone today at MW. Still doesn't change he isn't the same fighter he was then.
Golovkin was past his prime when he fought Canelo in 2017 like I said here Golovkin's prime was around 2009 till 2014 when he couldn't get his Titlefight with Felix Sturm and later moved to the USA.
You can't really ask this question here, its mostly GGG fans or Canelo haters on here, I recommend discussing this question on another platform, here the answers will either biased or pure hatred.