Steam also provides a lot more than just a store front for devs at that price, including customer support, multiplayer servers, anticheat, and forums and other social features.

Epic also launched their store without a shopping cart (you had to buy everything as individual transactions) and put new, unreleased games up for sale at up to 50% off without permission from the devs during their first sales event, amongst other things. Like buying multiplatform games to ensure that they only launched on the Epic store. Nobody liked it when Ubisoft, EA, Blizzard, or Rockstar tried that exclusivity crap with their own launchers/storefronts, and they don't like that Epic does it either.

Dude is a twat and his opinions unfortunately drive Epic's policies. People hated Steam when it first launched as well, but Valve as a company has consistently worked to put customer value and rights as a selling point of their products, and people appreciate them for that. Beyond Steam as a sales platform, they've been a driving force in other parts of the industry such as VR and Linux gaming.