Trust is not only relevant, it's essential for a thriving community. It is the glue that holds communities together, it allows for frictionless commerce, it lets us sleep with our doors unlocked, it lets us not spend billions on armies.
Anything that works towards degrading trust is "bad," is divisive, is not hugs & sunshine & should be immediately killed. With fire.
This is a prima facie truth that shouldn't need to be explained.
You have to keep in mind the technology involved here. Trust is non existant on its base level when you are dealing with anonymous people and a non reversable currency. In my opinion, no one can earn trust, its just a matter of what you can trust someone with statistically based on self interest. For example, why do we trust escrow agents? They could just run off with your money just as well as anyone else. Well, self interest is the answer. If they make enough money in fees, there is financial motivation not to scam. If someone gives me 1 BTC to hold in escrow, I could A) Steal the money or B) Not steal the money, complete the transaction, and get myself maybe a .01 BTC fee. Why would I want 1/100th of what I could scam? Because that party that is happy with my service will then recommend me to someone else, and I'll collect more fees. Generally, I trust people who have less to gain by screwing me over than they have to gain by being fair.
The trust system is not an exact science. Its a feedback system. I've traded with confirmed scammers on a regular basis, and I've traded with accused scammers. If I gauge that there is a risk to my Bitcoins, whether it be an unknown trader, or a scammer, I'm going to take appropriate measures. Thats not to say that someone couldn't buy a trusted account. But someone with an account worth 5 BTC, I might only trust them with 1 BTC. Theres no point in scamming me for 1 BTC and losing 4 BTC. If an escrow agent hasn't scammed someone for 100 BTC, because they figure they can make more than 100 BTC by operating legitimately, would I trust them with 100 BTC? Not necessarily. What if someone bought that person's account? Well, if the escrow agent values their name/reputation/service at over 100 BTC, a scammer is going to have to fork up more than 100 BTC to buy that account.
See what I mean? If you want a safer trading experience, use a website created for trading. The forum is first and foremost about discussion. We aren't going to inact any rules that benefit trading, if they could negatively impact the forum's primary objective.