I don't think you'll find many fully informed people who thinks that house reps trading on insider info is good (myself included), unless they're personally beneficiaries of that system.
But this discussion isn't really about that. The original guy asked "why shouldn't she do this?" She can do it. She benefits from doing it. No one will stop her. Why is it immoral for her to do it? Which is a totally different thing from "the majority of informed people don't want her to do it." To that end, she is behaving exactly as should be expected of her given the amount of power she has.
The only way as far as I know to get people to not make decisions that are bad for the world but good for them is to not let them have the power to make that decision. The US government has become an atrocity of corrupt and consolidated power. That's the problem, IMO. And so long as its leaders can spy freely on Americans, can take 40% of their income, can deny them rights, etc, then this is what happens.
My personal opinion is that this is immoral - and we're having this discussion because someone thought it was so immoral that they were motivated to write an article about how much they dislike it - but people write all sorts of articles so that's not a proof at the end of the day... Really, there are some things we can mostly (not all) agree are immoral like murder and rape - but even that isn't universally held (or agreed on to the same limit) because, well, some people do it. So yes - societal morals are pretty vague to define and I'm sure there are some people that feel fervently that House reps trading individual stocks is highly beneficial to society - but I feel like the majority of folks are on the other side on this one.