Yet you praise Punkbuster, which granted, was good at first. Hell, I stopped gaming online way back when MoHAA: Spearhead launched with no anticheat and became riddled with cheaters. Punkbuster offered to support it, but EA refused. I'd have loved to have PB back then, but they never went beyond a simple known cheats database. Such design is easily exploited by today's hackers, whom flood game servers with false positives, resulting in tons of unwarranted bans.
So put yourself in the shoes of the many whom got banned without reason and ask yourself, would you rather be able to play with cheaters thrown into the mix, or not even have an account to play on?
Again, I don't think you get how complex an issue this is. It's not as black and white as you make it sound. There's no simple solution. Many talk private servers, but there are problems there too. The pubs/devs have no control over private servers, and can be unfairly blamed, even sued, over what happens on them because it's their game being played on them. Plus at best they would only serve a very small percentage of players.