Tl;dr Steam is resting on its laurels and it's up to everyone else to compete with them.
The problem is they've all had a decade or more to do that, at least the last half of which the writing was on the wall this is the way the PC market was going and these are the features that customers have now become accustomed to expecting, but no one has been even moderately successful at it except for EA. And that's only because they're the 800 pound gorilla and they took their toys and left the sandbox.
Part of it is it's hard to get people to move when they're already entrenched at one place. But if the service and features were there and there were enough reasons I think it might slowly start to happen. But it hasn't because all their competitors are short sighted or lazy or incompetent or just give up and focus on Steam keys or sell their business to someone else.
There's also the fact that if there gets to be too many cooks it's not good for the consumer. You get these sites trying to push alternate clients like Playfire but who wants it? No one. Nobody wants to have 20 different clients installed on their hard drive.
What would be better would be some sort of neutral universal portable form of ownership that can migrate between sites like Ultraviolet. But that means all the players in the game industry need to get the hell over themselves and work together to some degree.
Either that or they all need to just look at Valve and Steam as the infrastructor that handles the networking, collecting, distributing, updating, social features etc. and consider that a cost of doing business just like overhead is for physical goods or dealing with Microsoft and Sony is for consoles, which is more or less what is happening anyway.
I think that we've gotten spoiled by being somewhat early adopters and getting all those deals that helped get people in the digital door. It's clear they don't need them as much now, obviously since Valve had the most users online ever just the other day during the lackluster (to us) sale.
At this point we've pretty much got to accept that the absolutely insane deals are going to be limited to indie games in bundles (many of which are quite frankly of questionable quality) and older games. I know that sucks for the whole game collector meta game, but people who buy and own that extreme many games that some of us do are honestly a pretty small niche of the Steam audience.
Anyway buying less games at somewhat higher prices is not necessarily a bad thing if we can re-train ourselves to be more selective and buy things we're actually interested and will play relatively soon. Buying a game at $60 that you get 100 or 50 or even 30 hours hour of is better than buying 100 games for $1 that you get 0 hours out of.
We all joke about it but I think for a number of us here re-examing and adjusting our buying habits really would be a good thing.