People also seem to be overlooking the benefits of downward optionality - you effectively transform a fixed cost (servers and staff to run them) into a variable

People also seem to be overlooking the benefits of downward optionality - you effectively transform a fixed cost (servers and staff to run them) into a variable one, that you can flex down cheaply (no long-term leases or redundancy payments). It lets you test things out (e.g. entering a new market) and cheaply wind them down if they don't work out.