"So you make a Steam Account. Big F'n deal."
No I don't.
"You make a similar kind of account to post here to El Reg."
No, I don't. Now if there was one company that handles logins for virtually every tech site out there, and if you want to post comments on any tech site then you have to deal with that company regardless of how shit their security is, and that company can then delete all of your posts over a server burp... in fact no, it's not even like that. I don't need to create any account to read El Reg. Your example, like the rest of your post, is, to put it politely, flawed.
"Don't want to post your credit card details? They have PayPal for that, or just use an online shopping card."
Why post anything? It's a toy.
"In return, it doesn't really matter which computer you use, just sign on, answer the "new computer" second authentication factor (which uses your e-mail), and you can download and play games just as you did on the other machine."
Or insert the disk, and play the game. DRM prevents me from doing that.
"Not a bad tradeoff if you ask me."
So making things more sucky for me, in return for absolutely no benefit whatsoever, is a good trade-off?