This is absolutely not the case for Bayonetta, she has full agency over her sexuality and expresses it out of her own volition.

Because the writers chose to write her that way. Dominatrix is a fetish, that's what Bayonetta is. A fetish. She is literally wearing a cat suit in the first game she has a whip that has a mask with thigh high belted heels and an enemy punish animation that solidifies all of this.

I can write a character, make her a middle eastern woman, and then write her to be utterly helpless and in need of a white man to save her from her "evil" culture.

I can do all of that, and if someone calls me out for reinforcing harmful and problematic stereotypes I can simply say:

Plenty of women do enjoy being perceived as submissive and weak beings, they enjoy the idea of being a damsel in distress. Helpless female characters in games are not inherently misogynistic.

Which is why I talked about who made Bayonetta, because that is what separates a character like Uncle Ruckus from being an actual Uncle Tom and a straight up minstrel show act.

And just to add:

My go-to example for this is Sonya Blade in Mortal Kombat 9, who is supposed to be a tough, no-nonsense military woman but who wears skimpy clothing for no reason other than, despite it making no sense for who she is as a character.

This reminds me of the "no black elves" argument. In fiction you can write whatever you want. There are no rules that you have to follow aside from grammer and punctuation. Bayonetta could have been written to be able to do what she does without nudity being used a reward for executing a certain combo or beating a boss.