What happens if, right when Anakin is standing over a defeated Dooku, and Palpatine says kill him, Anakin – doesn’t?
He spent a decade grooming and mentoring Anakin and playing to his weak points in manipulating him, he had a fairly good idea what he would do.
“So just stand there while I electrocute your son as he pleads with you.”
That was two decades later, Palps got arrogant and complacent and thought he had a greater hold on him than he actually did.
Then (presumably) Dooku is arrested, and (if he lives to see a trial), tells the galaxy that Palpatine is a dark jedi. Palpatine, presumably having been careful enough to have left no proof of these accusations, gains the political leverage necessary to escalate the war; what kind of monsters must these Separatists be if they’d throw such vile accusations at our beloved Chancellor? When Palpatine threw down with Yoda, we saw he could handle himself in a fight; had Anakin turned on him, he likely would’ve been able to hold his own- at the very least, until the the clones arrived, saw the fight, and, well, whose orders would you follow? Palpatine in the prequels represented a very different philosophy than in the original trilogy; more of a Kreia than a Revan, if you follow.
I suspect this change was made, not simply to make the character more interesting, but to make Anakin’s loyalty to him more relatable and forgivable. It failed, rather miserably; it’s easier to root for an everyman that’s simply tricked by a far cleverer leader than one who willingly marches into darkness, but a character who falls for a trick is less interesting than one who falls for a philosophy.
I was more thinking what if he says it right then, to Anakin?