He wants to sell his game for more on steam as to make the difference of 18%. So his idea is to offload the steam cut to the customers.
Yes ?
The base prices are determined by the market, by what people are willing to pay, nothing else, while sellers actively seek a price that will generate the most revenue.
Claiming he wants to rise prices on Steam even higher as a result of price difference is just stupid semantics, since it's actually not possible.
So, this is the idea that he sells for whatever he sells and customers who think Steam is not worth 18% gain opportunity to pay 18% less.
So there are two possible outcomes of the other platform selling 18% cheaper:
1) Most people will think that Steam is worth 18% and market share of cheap platform remains low enough for Steam to keep it's high cut.
Small minority of customers will get the opportunity to D1P 18% cheaper, Steam users loose nothing, devs/publishers gain nothing, Steam loses some small market share.
2) Cheap platform gains market share and pressure Steam into lower cut. Since the cut would be the same everywhere, prices everywhere would remain the same as they were before.
Customers gain nothing, Devs/Publishers gain better cut, Steam gets its cut reduced.
3) No one is selling 18% cheaper. No Steam users buy on the other service.
Customers gain nothing, devs/publishers gain nothing, Steam keeps its high cut.
The only side that has anything to loose in this debacle is Steam, while you have nothing to loose, but passionately defend Steam ability to cut deep into devs profit margin.
Not to mention he didn't back any of his claims with documents where it says he can't sell at lower price without steam keys/drm.
The slide Aruil posted may be fake news, so we will see. In currently publicly available Steamworks ToS there is no point on pricing at all.
I remember few years ago reading Steamworks ToS out of curiosity and price parity was indeed there without differentiating between Steam keys and other services.
Most likely Steam never actively enforced it, or the point was meant only for Steam keys and was unintentionally vague ( it's what they will claim anyway ).
It's all moot anyway, since as explained by VD in the other thread most devs/publishers are unwilling to make 18% price difference happen, since it doesn't provide any immediate benefit to them, while they are afraid that upset steamtards like you would refuse to buy their games.
So in the end they deserve to Steam charge them these 30%.