Isn't this essentially what CPS does today? The difference being that it's reactive instead of being proactive.
CPS can take kids from parents who are bad parents (drug addicts) just as they can take kids from parents who don't want the kids (and presumably would have aborted the kid if they could have).
Kids brought up with bad parents will be somewhat similarly disadvantaged. Why should potentially bad parents (eg. heavy drug addicts) not be banned from having kids? Both of them would be "forcing children onto parents who are in bad positions to raise them".