I don't know what this so-called "ban" is about. I bought a game on Steam last night and downloaded it - Terminator Resistance. I just got tired of waitng for this game to be discounted on GOG. There were several sales for this game on Steam this year and not one for GOG. Right now it's 50% off on Steam. Sorry GOG, I just couldn't wait.
I accessed Steam from within China two minutes ago and it's working fine.
I know pretty well how China censors it's internet. I've had to live with it for the past eight years. I can tell you with almost certainty that Steam would not be outright banned in China. They don't do things that way. Steam is very popular in China. And I mean extrememly popular. It would cause too much of an outrage to have a total sudden ban on Steam. When they want to ban a website that is popular in China or when a ban might disrupt business they do it in stages.
Some years ago when Google announced that it would no longer censor search results it wasn't blocked immediately. First gmail became unavailable for short periods, then longer periods to force people in China to use another email service. Then the Google website was blocked for short periods and then after a while it was completely blocked and remains so to this day.
If there was a short period of time when Steam was in fact "banned" my guess is that it was done to send Steam a message. Maybe the government asked Steam to remove a game from their website and it wasn't done fast enough. Or maybe they had some other gripe. The government likes to remind people who is boss. A year ago there was a foreign-owned hotel in China that had its website taken down for a week to teach it a lesson about toeing the government line.
In any case there is no Steam ban. It's open for business right now.
How it is to live in a country with camera st each corner with peoples ranking system for they behaviour? It smells like georges orwell 1984 book.