I completely disagree with this, because there’s a huge difference, and that difference is consent.
When someone is in a D/s relationship, they are giving their power to someone else as a gift. When someone is in a marriage where their husband is dominating them and controlling their activities and their body, they did not consent to that, it was taken from them.
You’re completely misconstruing what power exchange relationships are about. I love power exchange because as a woman who has to be in control and in charge the majority of the time, it’s freeing for me to give all of the power to someone else. The difference between that and, say, the abusive marriage I was in is that in the marriage I didn’t have a choice, and I didn’t have a safe word.