I have a number of thoughts in response to your remarks. First of all, I think it's important to acknowledge that there has never been any age or any society where every single person has had the same opinions. Certain attitudes tend to be common to certain eras, and some were encouraged or enforced by law, but there have always been a wide range of ideas and opinions, of behaviors and habits and beliefs. Particularly when it comes to nineteenth century, factors such as wealthy, class and where you lived could have a large effect on what was deemed normal and acceptable. For instance, the clash between "town morals" and "country morals" is vividly portrayed in Mansfield Park. What was fine and expected behavior among one group was not either in another. To use your example in the above quote, Trollope was a satirist. The fact that he writes about this proves that such attitudes existed, but it also proves that others at that time disagreed. He wouldn't be satirizing it if he didn't think it was wrong.
I think it's a fair question to ask whether "accuracy" is really always desirable in a story? Certainly realism cannot be considered the only criteria we use. How many of us want to read a story where Darcy has a mistress or visits courtesans while married to Elizabeth, considering it to have nothing to do with his marriage? Yet it would be perfectly accurate to the attitudes and behavior of many upper class men of the time. Of course you could argue that in creating him, Austen meant to make a man who would be of higher moral fiber than that (and I agree), but there is nothing in the book that explicitly says he wouldn't, and it would be historically "accurate." Nor would we want to read our favorite characters expressing the sorts of opinions on race that they would have in all likelihood hold. The past is in the some ways ugly, and while I don't favor romanticizing it to seem like all was perfect, neither do I have any desire to glorify or dwell on those parts of it that we have justly rejected. Does that mean that we should have our characters expressing completely modern opinions on everything? Of course not! But neither do we have to make them embodiments of the worst parts of our past, expecting modern readers to admire someone who says and does things we now find repugnant.
I think it's a fair question to ask whether "accuracy" is really always desirable in a story? Certainly realism cannot be considered the only criteria we use. How many of us want to read a story where Darcy has a mistress or visits courtesans while married to Elizabeth, considering it to have nothing to do with his marriage? Yet it would be perfectly accurate to the attitudes and behavior of many upper class men of the time. Of course you could argue that in creating him, Austen meant to make a man who would be of higher moral fiber than that (and I agree), but there is nothing in the book that explicitly says he wouldn't, and it would be historically "accurate." Nor would we want to read our favorite characters expressing the sorts of opinions on race that they would have in all likelihood hold. The past is in the some ways ugly, and while I don't favor romanticizing it to seem like all was perfect, neither do I have any desire to glorify or dwell on those parts of it that we have justly rejected. Does that mean that we should have our characters expressing completely modern opinions on everything? Of course not! But neither do we have to make them embodiments of the worst parts of our past, expecting modern readers to admire someone who says and does things we now find repugnant.