The problem is that while those would be interesting motivations, at no point in the actual movie is it stated or even vaguely implied that those are Shinzon's motives, so its pure speculation. What we got in the movie is that he wants to destroy Earth for some reason, and hates Picard, for some reason, both of which are never clarified.
Some of us got it by ourselves
. The clues are right there. Why do some audience members need everything spoonfed to them?
What's wrong with a little speculation after seeing a Trek movie?
"So why do you think Spock needed to rid himself of human emotions"?
"Why was Saavik crying at Spock's funeral?"
"Where was Amanda during Spock's fal tor pan
"What was the Probe asking the whales"?
"What does God need with a starship?" (Well, okay, that one was asked in the film. How about, do you think he was a rogue Cytherian?")
"Why does Kirk suddenly hate Klingons when he happily hosted some in ST V"?
And so on...