I think the 2wt vs 3wt nymph rod debate isn't specific enough. It's generally perceived that a 3wt will have more backbone and rigidity but that is not always the case. It's generally perceived that a 2wt is more of a specialty rod and a 3wt is more general purpose, the 3wt 10 footer being the preferred rod for most. For me, my 2wt nymph rod is my all-rounder (indicator nymphing and both tight-line) and my 3wt 10ft is my tight-line specific rod, of which, I have used for tight-lining only a few times, and in those few (less than 5 times) I wasn't very good at it. My 2wt tosses an indicator superbly and does dries ok, my 3wt 10ft rod is a very close range rod and more sensitive with that proverbial "heavy swing weight" feel I like in a tight-line specific rod.
In the future I will be purchasing a 2wt 11 footer and a 4wt 11 footer. The last time I fished on Penns I wanted a nymph rod with a bit more reach and I need to see if a 2wt will have enough backbone for that particular creek.
I think a lineup of specific rod models needs to be compared to provide a more accurate result. In modern times the blur between 2 and 3wt rods in general is quite blurred. Still, a good and insightful vid from our lord and savior.