^Except that the film ITSELF doesn't deal with it that casually. Had it done so in a consistent way, I would've at least enjoyed it more. Which is exactly why I don't think the film works. What you just mentioned is mostly how Iron Man deals with his **** and whether you like that style or not, they at least do it consistently – 'it' being playing fast and loose with your characters.
But you can't have spider-man go through tons of dramatic ****, try to establish villains that you care about in real grounded and dramatic way, approach them tonally with a heavy amount of weight, and yet whenever it's convenient to move the plot along, spider-man just rolls with it and suddenly it's a casual lighthearted superhero flick again.
That's having your cake and eating it too, writing-wise. This film should've chosen to be either Iron Man or The Dark Knight, either Avengers, or Man of Steel. You can't mix those two types of approaches to the material imo.
Yes there is a middle ground, in a way that the 90s TAS clicked for example, or Winter Soldier for example, which is really impressive in how it balances comedy and drama, both of them looking for this balance in a different spot, you gotta dial both tones back to a real balance that flows fluently and in which both tones 'respect' each other. That connect to each other. Instead we got Mr. Freeze (Rhino) in the same film as that kid from Chronicle (Harry). That's bizarre to me.
I'm sorry I don't buy into something that's that inconclusive in how it wants to approach the world it presents.