It's an appealing notion: who doesn't want to make life miserable for the greedy vermin who are constantly clawing private data and manuring the web with their pathetically awful adverts?
I suggest, though, that you need to think really hard before dipping a toe in this pond, because the Law of Unintended Consequences is always hanging around the next corner, aching to cause mischief. Even the amazingly evolved and effective human immune system is prone to going nuts, sometimes for no reason yet known to medicine, and attacking its healthy host. The analogy is only an analogy, but still something to give us pause while asking some pertinent questions.
Who decides what's bad and what's good? How are threats graded? Who approves the algorithms? Are responses proportionate? Who maintains a database of signatures for the immune system to respond to? How will that be kept secure? Which court arbitrates grievances, protests, unfair practices, loss of business, libel? Who determines what's a conventional option versus what's "nuclear"? How will false positives be managed?
I could fill a page with questions (as any fool could, indeed) but the answers better be given some serious practical attention before we go lighting the blue touch paper. (And don't forget the $64k question you always have to ask these days: How soon after starting this programme will politicians, corporates, governments, greedy opportunists and other fundamentally psychopathic entities get involved and completely corrupt its good intentions?) We could grow something in a petri dish, with the best intentions, only for it to turn into Mutant 59.
And there's that troubling term "arms race", which gets used with increasing frequency when talking about computer security. It is very apt, but one should remember where arms races usually lead: disaster for everyone, as all those weapons get used in a spasm of entirely predictable stupidity.
I don't have a magic wand as an alternative, but I will offer this: a key enabler of internet abuse—in which I include spam, malware, advertising, exploitation of user data etc—is that too much stuff is free.
Consider that spam wouldn't even be a thing if everyone had to pay even 0.1¢ per email (and the money could be used to fund all sorts of Good Things). Facebook wouldn't have to abuse its users (the ones Zuck calls "dumb fucks") if instead it made its money at $2/month or whatever. Don't Be Evil wouldn't have to epitomise rank hypocrisy if you paid $1 for every thousand searches. The 0.00573% of websites that are actually worth visiting because they have decent content would charge micropayments for use and not have to befoul our eyeballs with unspeakably shitty adverts. (And Twitter would cease to exist completely because grown adults would abruptly realise the pointlessness of paying to pump up their sad little egos by twatting out snippets of superficial trash.)
The internet is corrupted and ruined by "free". "Free", it turns out, makes people into victims.
The net would be a much better place if it charged a fair rate. Payment makes people into customers: with rights, dignity ... and the expectation of privacy.