Your response to criticism of Steam was ‘there’s other services.’
That does absolutely nothing to deflect from criticism of Steam.
Praising their various features comes a little closer, but still doesn’t justify taking an entire third of every game’s revenue. It takes a whole fucking lot of hypothetical work, which you imagine developers would have to do, to amount to the slice Steam takes right off the top.
What Valve offers that makes companies put up with that is their de-facto monopoly presence. They can sell many copies through Steam - or they won’t sell many copies.