Your OP have a lot of merit, I'll just disagree on the Sony Corp interference or demanding the shift in tone.
It was probably decision by the studio itself, unless you have some source or evidence for this because from all we know Sony allowed a lot of freedom for devs.
The shift for more mature themes and more violence in ND games have been growing ever since.
duduspace11 "Well, since we are estimating costs, Pokemon Red/Blue did cost Nintendo about $50m to make back in 1996"
Mr Puggsly: "Hehe, I said good profit. You said big profit. Frankly, not losing money is what I meant by good. Don't get hung up on semantics"