If 500 silicon valley engineers can replace 100,000 travel agents earning $50,000, then you have 500 silicon valley engineers earning $10m and 100,000 unemployed travel agents.
That's where the consumer surplus and company profit come from.
Second: freeing up the work of 99,500 people would be awesome! You know that nearly everyone used to be a farmer back in the day? Surprisingly, the world today is not made up of 70%+ unemployed farmers?
What is moral and also efficient and kind is not standing in the way of him finding another occupation - to remove all regulation that hinders someone from providing value