

I guess it’s more of a situation where they can’t penalize you if you buy and sell accounts.
But to answer your question, you would exchange your password for money and the account is now theirs with no fear that Valve will ban them for breaking a rule. They have to allow it but are not required to create functionality in Steam to make it easier.
That’s not true at all. People figured out how to get nexto bot to play for them in ranked games. I haven’t heard about it in a while so they might have fixed it.
There are also invisible car exploits. Also network connection manipulation. These cheaters rank up super fast so 99% of players won’t experience them, but there are absolutely cheaters.