@Shifty Geezer I think is deserving of a ton of criticism. People can view it as hostility, but their business model is run entirely from a position of a monopoly. They do not have a good reputation for listening to developers, from what I can surmise. I think the perception is you don't get what you pay for from that 30%. I'm sure devs would have the same complaints about Apple, Sony, Microsoft, but those are walled gardens and you really can't do anything about it. The same was true for PC. You pretty much had to be on Steam. Now there's another store offering a better deal and a large customer base, and people are acting like that's somehow unfair or bad for the industry.
From the dev side the perception is that steam has stagnated for a long time and does not provide value for money. They view valve as using their cut to fund other ventures like VR instead of reinvesting into the storefront. On top of that, valve justifies the 30% by offering features that can be integrated into games, but that integration costs time and money, so the features end up costing you more than 30%. Those features are not cross-platform, so the companies end up dropping them. They're paying 30% for content delivery in a store where they're not necessarily getting the prominence they want for the millions in revenue they end up giving to valve. Now there's a new store that will take 18% less, and provide more visibility to its customers. The decision almost makes itself.
You sell 1 million copies of a $60 game. That 18% is $10.8 million. Think of all the studios that have closed. That could be a life saver.
You've had a game market where the following is true:
Sony - 1 storefront
Microsoft Xbox - 1 storefront
Apple iOS - 1 storefront
Google Android - 1 storefront ... sort of. It's the default on the device, pre-installed
PC - 1 primary storefront
They all charge the same rate because they're all either walled gardens or effective monopolies. The fact that they all take the same rate is basically because they can't compete directly with each other and so they're price fixing. It may not be illegal price fixing, because they didn't necessarily sit down in a room and agree what the price would be, but it exactly why monopolies are bad. Now in the PC space there's at least some competition which is what gamers and devs had needed for a long time.