Imo Epic is the only competitor to Steam that tries to offer a similar service to Steam. It's just popular to hate on it among pc gamers.
Many people cite a lack of features on Epic's store as the reason, eg no forum feature, but then turn around and decry Steam forums as the worst place on the internet. I don't think the problem is a lack of features (for players, devs have a point), but rather the Epic Games Store isn't cool enough.
Now, once you open Epic you can ignore it, use Explorer open the game folders and launch the games and they run. So it looks like they literally need a way to change a config file to avoid re-downloading 100s of GB of games.
I find it literally crazy. They even scatter .egstore files around so actually scanning for and adding games to the library automatically should be easy.
Steam makes the same task easy, and why wouldn't it it's pretty rudimentary for an installer/launcher to have a easy way for you to tell it where your downloaded games are.
Oh, and the instructions for reinstalling Epic _launcher_ say to just re- download all your games. They're insane.
YMMV.
Steam for example, allows user submitted ratings with explainer text. This is huge for online shopping decisions.
Steam Workshop is easy to integrate mod distribution for games. Etc.
I don't know anyone who actually relies on Steam ratings/reviews to make purchasing decisions. I've always assumed that rating systems on the platform that is selling you the product are not trustworthy. But then again, I find reviews for media to generally be useless.
>Steam Workshop is easy to integrate mod distribution for games.
That's a developer feature rather than a player one though.
Steam also has the features to do social proof of reviews. The reviews contain metadata about if the person got the game for free, and if you click the profile associated with it, you can see all the games a user has played and their achievement progress, which can help signal if they are a real gamer, how far they've gotten in the game they reviewed, but also how far they get in other games they've played to check that they're not a sock puppet.
This has enough value that Epic displays a star rating that is allegedly user generated, but because it doesn't indicate who is doing the reviews, and there is no text, their star rating is a lot more suspect.
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Modding support is also a player feature. Official, well supported modding can make or break a game, and Steam facilitates quite a lot in that regard; Nexus, as an alternative, is ad supported and caps download speeds for mods unless you shell out for a premium membership.
Arguably, it requires an account, and has things like "number of hours played" included in the review.
Far, far more useful than the easily-gamed spam reviews on places like Amazon. Doesn't mean spammy things can't happen, and the aggregate reviews on Steam usually mean what the 14-24 year old demo think
How is Epic a serious competitor or alternative, then?
The problem is that Steam for all its faults is DRM, anti-cheat, and a well functioning store rolled all in one. Most of the alternate stores are bad in one way or another; Epic launched without a cart, and it still doesn’t have user text reviews. Itch had to redo its whole UI after that one bundle they did that had thousands of games in it.
Notably Valve doesn’t really use its position to make competing games. This is an unknown for most publishers, and Epic pretty blatantly pivoted Fortnite to eat PUBG’s lunch after working with them.
If anything the leading platform for competition as an indie store is the Nintendo eShop. Which is probably why the Steam Deck exists.