I've got to believe that after all this time there are all kinds of statistics on delays, weather patterns, and so on. Taking those into account, a nice cushion of spacing can be taken into account when scheduling flights across the airlines.
Instead, the schedules are set up unrealistically in pretense that the weather is always fair and clear everywhere.
So when bad weather comes, instead of pointing to unrealistic (and economically unsound perhaps when the wheather IS fair) scheduling plans, we can blame the weather with impunity. Or else blame the passengers, since we are only responding to demand by scheduling all those flights.
I mean, how many inconveniences must be put up with before a reasonable person can conclude that, yes, weather happens, and we can expect it to continue to happen in the future.
Something in me just can't see the airlines as completely blameless in this, must be that streak of pure cussedness.