I'm less bothered by the "it's still Kratos" aspect (I don't expect Sony to drop one of their titular characters and IPs for something "new", that'd be stupid), and more bothered by the "how the hell do you fix all the shit that went down at the end of GoW3?" aspect.
"It's not something new" is an argument I've seen more and more people run with, and while it does have some merit I mostly regard it as petulant whining.
"God of War should stay as God of War" is crap because there are multiple gods of war throughout human myth and history. That it went with the Greek one first doesn't invalidate Agurzil or Mixcoatl or Chi You or Ahnur or Chamunda or Hachiman Daimyōjin or Belus or Qamaits or Odin or Freyja or Bellona or Anat or any of the other war deities/pantheons. It's purely an argument of "I want something NEWWWWWW!" and smashing one's fists down on the table in frustration, because there's no actual argument that rationally favors it.
Would I find it interesting if they'd still retained the GoW name, but came up with a new protag? Of course I would.
Would I be irrevocably buttmad that the literal son of a literal god among gods managed to survive an injury he's survived before and went on to live out his life elsewhere since he's probably some form of immortal or just has a really long lifespan due to his parentage? Not really, because I'm not so uptight that a new spin on an established character in a new environment sends me into a Fury (see what I did there?), and that is the only way I can regard the holders of this particular argument--it's not so much me knocking and dismissing them or the argument outright, but rather dismissing it due to how opinionated it is. There's no set rule that the studios have to do something new all the time--we then run the risk of audiences equally blowing their tops because the new product deviates too far from the expected standard of quality.
Does recycling Kratos illustrate a possible laziness on the part of Sony? Of course it does. We live in a time in the industry where shit's getting recycled left and right, with a lot of it being lackluster straight out of the gate. Of course people are going to be defensive and wary of another instance--but, despite that, dismissing the validity and worth of something almost entirely on that premise alone is a show of intellectual dishonesty, since the root argument is purely a subjective and opinion-centered one.
I, for one, am curious how the actual Hel (see what I did there?) they're going to explain how the world was restored after Kratos offed practically all the major terrestrial deities and caused armageddon in the process, survived the suggested death wound, survived the very long fall off that cliff he was implied to have fallen from with that suggested death wound, relocated to (presumably) somewhere in the Scandanavia/Denmark/Iceland area, had another kid presumably lost the wife/mother after the implied apocalypse happened, and where and how the Norse pantheon show up.
I don't really give a shit that they're recycling Kratos for his titular series. I fully expect that sort of thing. I fully expect for Sony to milk the franchise as long as they can as has become a bit of a disappointing norm--but looking at who's working on this, and specifically who's leading it (seriously, Corey's back to man it, I don't see how that can possibly go badly unless he's done a complete 180 on his quality of work from when he led GoW2), I can forego grievances about recycling characters again perhaps where it's not necessary anymore because I expect the game to actually be good.
This sort of argument looks a lot like all the outcry when Heath Ledger's Joker was first shown to the public--everyone bitched and moaned that he'd never live up to the likes of Nicholson and Hamill and that it was a waste of time and effort and would be so horrible, and then The Dark Knight came out and everyone shit their pants praising the performance.
What is this argument doing? More or less the same thing--people bitching and moaning that Kratos is being used again and that it's not "original" despite literally everything but Kratos being a completely new setting and that the game is somehow ruined on that premise alone, all before anything more than the E3 demo has been shown, before there's anything really solid in Gow4's corner.
I'm not a particularly big fan of the "don't knock it until you play it" counter, and am trying not to veer into that territory with this, but the hostility and defensiveness of this specific argument seems a bit of a jump of the gun, don't you think?