I think the fact that people can just make a new account anytime they want and start posting or commenting makes it very "easy" to spam. I've had that opinion since quite sometime but didn't say anything but today something happened which makes me think that this is of extreme importance.

Commenting from a new unrated account is like saying stuff without consequences : When you've given a few contests and spent some time on your account then you have an identity. Making a new fake account is equivalent to wearing a mask.

Take for example today's incident-

So there's this blog on codeforces "Code For Athoy — Contest for Saving a Life". It's basically a contest announcement as well as a person asking for donations for a cancer patient.

Now on that thread I see an absolutely insensitive jerk, just look at the audacity of this person. Here's his comment

While banning unrated people won't end spamming completely it'd definitely reduce it, plus I don't think it'll be hard to implement. There's no reason for not banning them, after all, unless you haven't been a part of any rated contest, you're not really a part of the community anyway. I believe this one step would go a long way in reducing spam posts and comments to a great degree.