I think this whole problem hinges around whether the reader wants it to be a problem.
Or, to put it a less awkward way:
If you like playing characters that have relatable motivations, then there is a good chance that you will have problems with some of the writing in GTA. The level of discomfort will be correlated to the amount of inflexibility you have on this issue. If you really don't like playing as a heartless bastard, then yeah, you will have problems.
And that's not necessarily a bad thing. I've seen people who didn't want to buy Payday 2 because they didn't want to play as a bank robber. Nothing really wrong with that. I'm not those people, but I understand where they're coming from. They don't find the idea of committing imaginary crimes fun. I'd be slightly curious as to whether they knew this ahead of time and, if so, why they bought GTA V. But then again they're supporting video game developers and trying something new, so who gives a damn?
If you don't mind playing as a criminal, and a lot of the people buying GTA won't - that's why they're buying it - (and this is where the 'what did you expect?' argument comes from) then the complaints may seem ludicrous. But they're not, really, they're just coming from people with different mindsets.
And that's where the gap comes from. Personal taste. I mean, I don't think GTA V's story is *objectively* worse than GTA IV, whatever that would mean. I actually had more fun in V. At least the characters' actions when the player controls them are better explained in V. It's been talked to death but Niko didn't make sense a lot of the time because he'd be whining about war crimes while driving full tilt down a sidewalk.
So yeah, this whole argument comes from two groups of people not being able to understand the complaints of the other. Which is how a lot of arguments get started, but there you go.