The trust system is hardly broken just because of one or two ratings. I wouldn't trust someone who has such opinions but I'm not going to leave feedback for it either but the feedback system is there for users who you feel you trust or distrust for whatever reason and that is of course subjective. BadDecker seems more like a troll to me anyway but either way he has some despicable opinions.
I've seen many weird trust ratings while bored waiting for the post timer to conclude when I want to post something right after having posted something a second ago.
Some people have negative trust, but the amount of BTC involved is literally 0. And the negative trust message is somewhat odd, something like: "POTENTIAL SCAMMER! ASKS FOR NO COLLATERAL LOAN"
This is odd to me. If he never scammed anyone yet, then why does he get negative trust that reflects oh so poorly on his main profile when posting? That's unfair to the maximum.
If a stranger knocked on your door and asked you for a loan would you give it to them? People often see random users trying to secure a loan over the internet as pretty shady. I would say probably at least 98% of these people would just disappear and never pay the loan back should they get it and that's why they get the negative feedback. You could argue it's unnecessary as probably nobody is going to give them the loan any way but there's a lot of people who think they deserve the feedback as well.