Oh come on, comparing Steam to telecoms is a bit of a leap. Nobody needs access to video games on a day-to-day basis. Video games are a luxury item at the end of the day.
Their breaking up also assumes that hosting video games for downloads is a thing only Steam can do. Steam hosting the game files and Steam as a service for the customer have little to no relation to each other. Steam, or anyone else for that matter, could just as easily use AWS. Breaking up Steam into many, smaller Steams might lead to lower prices, or devs will choose one, that one will become the dominant one, and we're back to square one.
The best way to drive prices down is competition. It's economics 101. Do not blame Steam for being successful, blame their competition (Epic in this case) for being inept. Epic was the VC baby everybody was banking on going toe-to-toe with Steam, but they couldn't even get basic shit like a cart or a wishlist working for far too long.
Steam's 30% cut is a different problem altogether. Yeah, it's probably excessive, and would ideally be tiered by sales. However, all the games (that I have seen) that released on Epic first, with their paid exclusivity, eventually came out on Steam. So what does that tell us about how impactful that 30% cut is. Steam's pre-existing userbase is a factor. Userbase they have, and maintain, due to their wide array of features. And, all those features Steam provides aren't free to maintain. They host the game on their own servers, they host all the user generated content on their servers, Steamworks matchmaking is ran by Steam. Game devs aren't just getting their game sold through Steam, Steam does much much more than that.
This is so painfully close to being Loss. There's got to be a way to juggle those squares around just right.