I mean... would it? Indie devs not only existed before Steam, but typically have a hugely contentions relationship with them. I haven't forgotten all the growing pains about races to the bottom through sales, arguments about curation and the entire Greenlight fiasco.
I'd give them credit for pushing indie devs enough to get Nintendo to stop being annoying to work with, but that was Microsoft pushing Sony which in turn pushed Nintendo. Steam is background noise in that process.
Valve solved the issue of PC piracy in the way Netflix solved the issue of TV and movie piracy: by creating a convenient service people liked to use that is significantly more hassle free than digging through shady websites. If they hadn't figured it out, the next-in-line big store that happened was GOG, which is coincidentally a DRM-free storefront that grew as a reaction to Steam. I don't know what the CD Projekt Deck would have looked like, but we at least would have gotten a third sequel of a game series, so there's that.