I didn't say anyone has special treatment. Everyone in DF is paired with random people, and everyone is subject to the same luck. DF isn't designed to have anything enforced. That's the whole point. You go to DF when you need roles filled quickly, filled by other people who are in the same need. That's it. It's not about making the run smooth for person A, person B, or person C. It's a group of people formed because they didn't have an easier option. If you want it to be smooth then it's up to all members of the party to communicate, like adults, and come to a compromise. Nobody should be segregated and told "You really aren't very good so you should only play with others who aren't very good." That would be as stupid as me petitioning to not be queued alongside those with ugly glamours. And yeah with glamours someone may think they look great while I think they look horrible, and it's the same with skill; just because you think someone is too casual, does not mean they think they are too casual. So they would still queue with you. Which, still, doesn't give you the right to remove them from a run because you two disagree on their skill level.
I am not saying anyone WOULD be forced to help new players. I am saying as the system is now, sometimes, you DO get forced into helping new players. Which is a good thing. You would diminish that possibility happening, in an exclusive "pre-cleared queue" which is a bad thing. If someone is new they should be able to DF something to have it cleared, and have a reasonable queue time. Hell even if someone is bad at the game they deserve a decent queue. The elitist comment is neither here nor there because leaving DF as it is now, or changing it to your idea, or changing it to anyone else's idea, won't keep negative people out of the DF. And the basis of your argument is a bit elitist in itself because it appears you are presenting the idea of "But I have already cleared this dungeon so I really shouldn't have to waste my time with those who aren't as practiced as me."
So, why do you want a system that protects you from yourself instead of bettering the community? You don't need to be toxic, you just need to communicate. I realize effort doesn't change skin color but the underlying mindset is the exact same: "I don't understand how to confront someone different than what I know so the systems should be in place should keep them away from me... but make it a little better for me because I view that I am the superior and they are the inferior." Like instead of petitioning for the system to make us all "play with similar people" maybe like, idk, become one of the people who asks someone "Hey are you new?" or maybe, idk, "Hey did you know you don't have to spam that move?" or "Could you please not use HoTs so often? It's making it hard for me to hold aggro." If someone mouths off to you if you ask, then kick them. If they are ignorant, teach them.
If you just want to keep people away from you so you don't feel taken advantage of, then stand up for yourself and don't let people exploit you. Don't just ask the entire system to essentially force players to segregate themselves into similar groups just because you don't know how to respectfully confront a stranger.