Not even close. Michael Nunn James Toney Bernard Hopkins Roy Jones Julian Jackson Gerald McClellan Jermain Taylor Kelly Pavlik Sergio Martinez Just to name a few... ALL better than Triple Duck.
"Not even close" - true statement, because of the first half of your list. The second half are by no means all clearly better than Golovkin. Perhaps if his career ended abruptly today, you could say they all had better reigns, but give him a chance. On his present trajectory I see no reason he can't rival or pass everyone below Jones on your list.
Yes. I definitely would say so when I look at peak Hopkins, or at the MW division during the early to mid 90s. Scrubs like Nunn, Toney, Jackson, RJJ, Parks, McCallum, Kalambay, Watson, McClellan. They could only dream about being as good and proven as GGG.
The fighters on the second half of my list ALL clearly have better *resumes* - and that, my friend, is ALL that matters. Call me when Triple Duck fights someone with a pulse...