Yes it should! I don’t want the game to tell me how to run my airport! A warning is fine, but definitely no restrictions. I don’t want to have to build a parking space before I can buy a car.
No!
And if they cause traffic jams, then it is the ACEO’s responsibility to do something against it, not the game’s job. The game does not have to tell me how to play it good.
You do have a point here. But just not to scare the noobs? How about some decently prepared default rules?