I buy from GOG sometimes, because they also have a unique value proposition with their anti-DRM stance. Other than that, Steam simply provides the best service by leagues, and it's very take-it-or-leave-it when it comes to the 30% cut.
I personally would love for them to reduce their cut, I think 30% is massive. It is worth pointing out that the 30% cut is well-established in many industries outside of gaming, such as franchising. But it's also fairly standard within gaming.
- Gamestop, Amazon, Best Buy and Wal-Mart take a 30% cut.
- PlayStation, Xbox, Nintendo each take 30% from their console stores.
- GOG, Microsoft take 30% from their game stores.
https://www.ign.com/articles/2019/10/07/report-steams-30-cut...