They arent acting like nothing is going on. They have already overhauled their entire launcher/store so it is more like Epic/Ubisoft etc. So the competition is forcing their hand a little. (coming soon)
But they wont announce "we dropped our cut from devs to 15%" as its a sign of panic which no company will do, they are too proud for that. I guarantee there is frantic decisions going on behind the scene.
throw in the absolute disaster that is Artifact that has to go back to the formula table.. its not pretty for Steam right now.
Steam's UI update has been a long time coming, but it was always coming. The whole reason behind them dropping XP support was to bring forward a new UI, which we first saw glimpses of with their updated chat system.
Their UI change isn't because of Epic, but it has undoubtedly been accelerated by it.
You are right when you say that Steam doesn't want to drop their cut, as that will quickly create a race to the bottom and everyone loses in that situation. One cut too far and we have a failed launcher on our hands, and that would be killer. They need to be cool-headed and only reduce their share by a manageable amount. Then they need to convince developers that their extra cut is worth it.
What Epic is doing right now is what many people want from Steam, a curated platform with a selection of good games. ATM you can be confident that games on the Epic Store are pretty good, which is something that cannot be said of Steam. On Epic, devs get visibility and gamers get a level of quality assurance that Steam lacks, which is a big deal. If they get through their store roadmap, they will be at a similar level to Steam in terms of features within the year.
Over the past few years we had seen Bethesda make a launcher, Activision jump on Blizzard's Battle.net and CD Project test the waters of exclusivity with Thronebreaker: The Witcher Tales on GOG. The big publishers were getting sick of Steam, and Epic Games has used that to secure themselves a solid position using the fortune that they have amassed through Fortnite.
What does Valve need to do now? Not sure. They need first party titles, but that would take too long to sort out and wouldn't be a quick reaction. With Discord in the picture, it is hard to see better chat features helping Steam in the short term. Perhaps a cut in revenue share would help, but with the amount of crap on that store I can see a lot of games never making money for Valve.
ATM the best thing that Valve/Steam can do, in the short term, is avoid bad press, which means better curation. They don't need another game like "Rape Day" appearing on the storefront. That's what they need to sort out, ensuring that that never happens again.
Epic cannot buy exclusives forever, Fortnite isn't an infinite money pit, but if they can last long enough to become a proper rival to Steam with feature parity, a large audience and enough data to prove to publishers that they get good sales; they have achieved their objective.
