The unusual though possibly wrong thing that differentiates steam is they don't appear to engage in all that much anti competitive behavior. Possibly some, but not really that much. Ultimately if it's better for the consumer but worse for 'the economy' who's really losing out? By what metric?

For now, at least. But the secret to valves success here doesn't appear to be very closed source. A fairly flat internal structure, moderately functional store and community reputation building, mostly keeping promises and having which reputation that when they don't they can weather the storm. Nothing there seems unachievable unless your design philosophy is so cut throat and monetized that you just build a bad product.