Well we can't disregard what was said in Part 1, Power scales changed yes, but that would mean that Hiruzen would have had is power scaled up as well... Him defeating the edo hokages was a necessary thing for the plot to move on....
As for their hype, Tobirama hasn't been mentioned a lot either, nor does he have any hype to compete with Hashirama/ Hiruzen... He is mentioned one or two times but only because he created edo tensei.... Other than that , the last time we got any hype from him and his power has been what? part 1 ?.As for Hashirama, he really wasn't mentioned that much at all, In part 1 we got the basic story of the hashirama vs Madara fight and that was it. He is now getting his time to shine through Madara.
I will admit however it does look bad for Hiruzen. Some of the Moukoton abilities Hashirama has coughed out makes it hard to believe he could counter them.... But even kabuto commented that in the past other ninjas were on Hashirama's level.. So There is still some hope.... A man with thousands of jutsu and such a wide arsenal of abilities I'm sure would have something up his sleeves to deal with his former master's abilities... He also seems to know their jutsu quite well and know the appropriate counters..
It is a stretch, And there is no solid statement from kishi saying that anyone WAS the strongest hokage... Only opinions of people in the past.... But I do believe there is a reason they considered him the strongest hokage despite at least tobirama dying not so long ago.
If what was said in part 1 was so important than Hiruzen's scale of power would've been upped and it would've been demonstrated somehow but it wasn't. Yes the scale of power would've been upped but there was no instance in the second part where it was, which has lead me to my conclusion (opinion of course) that Kishi changed his mind about Hirzen being the strongest Hokage. If for anything, Madara and Hashirama are the examples that prove my point tht he's not the strongest nor was he ever compared to his teachrs in their prime (in the scaling of power). What I'm trying to say is that Hiruzen's hype in part 1 was only for the sake of the plot as you said, however the section of the plot it was working for was not to show that Hiruzen=strongest Hokage. The section of the plot it was meant to show was how the Hokage were supposed tower over every other shinobi. They were supposed to be the rocks. Hashirama and Tobirama were the images of the past and were not supposed to win because they were merely shells. Edo Tensai recieved considerable hype and power increase as well and I don't man from Kabuto's fiddling with it but from how it was portrayed and represented later on.
Here's the thing with me and hype. You have the rumor then you see a sliver of the power behind the rumor but nothing else and you're left to make your own assumptions and grades etc. Tobirama's hype does not exceed Hiruzen's in the sense of rumors and titles, but as far as those slivers of power demonstrated (the vauge feat to back them up) Tobirama's surpasses Hiruzens. Lets take a look
Tobirama
Rumos: Strongest Shinobi of his time (that's about it)
Support: Creation of Edo Tensai and usage of sed technique to be renown as the shinobi who created it (Mu, Kin, Gin brothers, Hiruzen, several shinobi around his time) | ST techniques that are worthy of note by another Hokage in comparison to his own and that Tobi, where as the latter two possess arguably the most powerful ST jutsu thus far | Suiton Mastery unlike any other. His powers to create Sea like masses of water in thin air and to preform techniques with only one seal consider the possibility of his powers with water around him.
Hiruzen
Rumors: God of Shinobi (shared title) | The Professor (knowing all of Konoha's jutsu) | Strongest Kage of the Leaf in Prime
Support: Katon and Doton mastery to the same extent we see of his pupil Jiraiya | Reaper Death Seal | Defeating watered down Kage and former student who played with him for a majority of the fight....
If you look in compariosn to the feats, who can you say has the stronger hype in that department? Certianly not Hiruzen. He has no supporting feats to prove these high aclaimed rumors about him. God of Shinobi? He shares the title with a man worthy of the title. What completely devestating powers did Hiruzen have? What were all these other jutsu that Hiruzen possessed that he supposedly mastered?
It is imensly difficult to argue for Hiruzen against either Madara or Hashirama. I don't remember where it said Hiruzen had 1000 techniques...nor do I know of any techniques that could be within his arsonal that has the potential of power that were demonstrated by these two demi-god like shinobi. Bijuu level Susanoo? Mokuton abilities that can create, essentially a forest, complete control over Bijuu? What could you possibly imagine within an arsonal for a shinobi like Hiruzen to have to deal with these types of techniques and powers?
Kishi has gone back and contradicted a few things I believe from reading other threads, even the power scale his him going back on what he previously dictated in the story....so what is to say that what was said back then still constitutes now? For plot a lot of things were done, and I believe using Hiruzen as a symbol for the plot then (which was less complex than it was now) was all he meant for. The plot of Naruto changed dramatically from a ninja fullfilling his dream to a more dynamic straight viewd concept.
In part 1 Naruto and the gang would go through various challenges that were to show Naruto's growth and had no one direction until the middle of the chuunin exams. It soon became about Sasuke leaving and going with Orochimaru then in part 2 it became about Akatasuki and it's been drawn out so much now. Things have changed and a change I firmly believe is true is that Hiruzen is no longer the strongest Hokage in his prime.
