Flying is something that many of us cannot reasonably avoid, so every time airlines take away another inch of legroom, add another fee, or force someone off the flight they paid for because it was purposefully overbooked, we suffer. Deregulated airlines will continue to give us less bearable flights, more fees, and make other changes to make themselves more money and remain competitive.
It shouldn't take paying thousands of dollars for business or first class to be treated as little more than cargo. We should not have to endure uncomfortable flights that are only getting worse so airlines can increase their profits.
We want the airlines to treat us fairly, and since airlines will not on their own, we want them to be regulated by the government.