I dont think the experts will agree he's shitted on anything to do with Pacquiao. He's closing in on him though. I already think Canelo is Floyd's best victory. If Canelo goes on to achieve a lot after this, then Floyd will at least have a great W on his record.
Unless or until Canelo proves me wrong and goes on to do good things after this, I actually don't rate this scalp enough to bump Floyd up that much. Honestly, I don't really rate Canelo that high as a fighter. That doesn't mean that Floyd didn't look good in there though, or that his performance wasn't impressive given the context of the fight (his age, his hands, canelos youth, the weight, ect) So it adds to his legacy, no doubt. But really, I don't see why this fight would make any truly significant change in his ranking historically, unless someone is really overrating Canelo. If Canelo wins up winning big fights in the future Ill change my tune for sure though.
Unless Floyd takes on and beats a couple of great fighters, his legacy will forever be marred. Hey...even Brian Nielson had a longer winning streak than Floyd, yet nobody refers to him as a GOAT.