That was a poor analogy. Dao alone was targeted, not the entire plane. The pilot was never involved.
United wrote their own Terms of Service. According to their own rules, they had no right to eject Dao. If that’s problematic, then they need to thoroughly rework their ToS.
The principle is the same, whether it’s one person or more.
So let’s say we land in Kansas City, and the pilot comes on the intercom and says, “Fantasywriter has to get off the plane. After Fantasywriter gets off, the rest of us are going on to NYC.”
Are they breaching the terms of your ticket? You bet.
Do you have the right to physically stay on the airplane after being ordered by the owner to get off? No you do not. If necessary, security will drag your ass off the plane, and it is perfectly legal. You can sue them for your monetary damages for failing to fulfill the contractual terms of your ticket by not transporting you all the way to NYC.