It's the industry standard for online PC game sales because of them. They established that number when they were the first major player to the market. They don't get to blame the industry for a pricing scheme they invented.
This is the company that didn't offer refunds until they had to. They're the company that used to make indie developers get permission to launch games through them with exclusivity agreements (Steam Greenlight program). They cry foul when devs put in loot boxes, gacha mechanics, and other live service bullshit when they don't get a 30% cut.
They've been exactly as shitty as they can get away with. The only things that have allowed them to be less shitty are that they were first to the game and that they're privately-owned l, meaning they do what's in Gabe's long-term interest instead of having to drive the stock price up every quarter until they collapse or allergens with someone else.
When Steam launched, gamers were very upset because they didn't want to have to log into an online marketplace to play Half-Life 2. And now people get pissy when the games they want dont require you to give data and money to a billionaire who long ago stopped giving a fuck about gamers as anything other than a means to buy more yachts.