Outlander is a guilty pleasure. I have a bit of a love/hate relationship with it.
I'm delighted with the concept, and how well the time travel is handled. It's fun and fascinating to see the family flit between eras and cope with the challenges of their multiple times. Historic detail is deftly handled, for the most part, and there's just enough interaction with actual historic figures---not so much that credulity is strained.
Every now and then, however, some small thing occurs that yanks me out of my happy suspension of disbelief and makes me yell at the page, screen, or audiobook narrator. (Yes, I've indulged my guilty pleasure in all three forms.)
The only example that comes immediately to mind, is what I think of as the fichu fiasco. The horror of it drove details from my mind!
I'm sorry I don't recall the exact circumstances, or even in which tome this occurs, but a woman takes off her fichu and uses it as a rag. Someone had a sweaty brow, or was bleeding, or muddy. And Claire or some other woman whipped off her fichu to wipe it up.
She wasn't a woman of substance, with a plethora of neatly laundered fichus waiting for her at home, nor was she such a light woman that she would really have been oblivious to the shocking scandal of taking off her fichu in public and going without it for the rest of the day. It was, given the laundering realities of the day, even less likely than for me to take off my blouse and bra on main street to wipe someone's blood or mud away.
I wouldn't do it. I would wipe the blood or mud up but I'd find something else to do it with.
So when this scene first presented itself to me, what I do remember clearly, is that I yelled out loud, "She did NOT!"
As distressing as such out-of-character, out-of-time moments are, they are not the worst. Of greater concern than the fichu or the famous spanking scene you mentioned, Tatiana, is the rape culture. I suppose it's realistic, that such a large proportion of people in the books were raped. In that time, or in this, rape happens, way too much, and doesn't get written about enough. So it's not just the fact of rapes that troubles me.
I appreciate a lot of how Gabaldon handles the rapes, too. Victims suffer realistically from PTSD. There are broad consequences and deep scars to go with the rapes, for the most part. I find I can't write more than that without a bit of spoiling, so, -> Spoiler Alert <-
I couldn't forgive her rapist along with Brianna. I know he got his in the end, fine, but the scene where she visits him in jail just doesn't ring true for me. She should want him to die slowly and painfully, then and there.
And then there's Fergus. Child rape, shrugged off with savoir faire, just isn't realistic, when we know that victims of childhood rape tend to grow up to either commit child rapes themselves or be victims in abusive relationships later in life, especially without counseling. Sure, Fergus grown up isn't the easiest mate, he has his shortcomings, but he just doesn't seem to be as haunted by having been repeatedly violated as a child, as I would think probable.
So, sometimes the Outlander books make me squirm. But sometimes I find them thrilling. And the thrill is not only from compelling storytelling of fascinating adventures. There are moments of depth, poignancy, that raise the whole thing above the level of confection, and clear up to art. Gabaldon uses her wild, centuries-hopping tale to reach real truths about the human heart and soul, and then, of course, I have to forgive her for everything---even the fichu fiasco.