Your flight is delayed because we are about to make a few passengers with tight connections happy.
I've seen that too. It sounds like a contractual statement, in my non-lawyer opinion. As in, they openly stated that they were committed to ensuring these passengers (like the OP, in this case) would be on their connecting flight. It was a voluntary utterance. It was specific to a particular situation. Companies should not be able to get away with making promises like that and not fulfilling them.