If some of the more disruptive cases can be diminished seems that like that can be worthwhile.I think the point is, why bother, since the net result will be the essentially the same number of spam posts but users now having to do more reporting to capture them. At least this way by not having a throttle most spammers can be caught by a single report.
All throttling will do is make it harder to report them. And that means the spammers win.
I mean by the same logic why bother with the existing limitations in time between posts and reports, for example? Or many other things in life that don't prevent everything or only help with just certain circumstances and nothing else?