I do agree that one should take steps to protect themselves, however they should use means that they feel work for them. Just because someone suggests private proxies and not to rely on "stupid little programs like PeerBlock" (which I feel was going a bit too far) doesn't mean that's the only way, nor does it mean programs like PeerBlock are truly useless.
There's more than one way to protect one's computer. There is no such thing as a "true, one way" of doing anything. You can ask for advice, but there's no reason to treat what they say like it's the only truth. As I said, there's many programs and different techniques available to help people protect their computers.
One example of a type of program that may be useful is browsers that allow you to surf the web anonymously. Yes they do exist. PeerBlock, on the other hand, blocks out IP addresses and does offer relatively quick updates. I never use my computer without it turned on. If you don't think programs like these work, then okay you don't have to use them. My point is there's never just "one true way" to do something on the computer.
My best advice I can give in this situation is, before deciding what you're going to do (whether it be using a program or a private proxy), do some research on both and see which one you feel works best and makes you feel safer. Don't rely simply on what one person tells you. Even any program I suggest may not be for everyone.