I'm not really sure why the daytrading rule was put into effect. All I know is that it was not to protect the small time investor or "support the risks" associated with daytrading. The daytrading rule as it currently stands forces me to hold positions overnight, why? The brokers are happy to extend margin to my account. What if I buy a penny stock on full margin and the price drops to zero (I've seen it happen), what then? Are they going to restrict penny stock purchases too, because it's too risky. What if I buy a stock that's trading at 300 times P/E (seen it) and it crashes, what then? Are they going to restrict high P/E stocks too?
By the way, the daytrading rule does not state how many positions you can open. You can open any number of positions as you want, as long as you don't make more than 3 same day roundtrips in a 5 day period.