Cheating at "rapid" \ "standard" controls

I have played 39 rated rapid games on lichess, and 4 of them were cheated by the opponent.
So yes, there are cheaters, but they also get banned quickly.

...and they create new accounts even quicker :P

Eventually IP ban will be the only solution left.

IP is also floating, you can not calculate. We need to look for them in real life and to heat in the toilet.

Is it also possible to block their emails so that they can't create a new account?
I know, they can make more emails, but some time it will stop, right?

SMS account confirmation to start?

IP, Facebook, ID or SMS... one of these methods would significantly reduce number of cheaters

Possibly. But reduces the number of users to a couple of hundreds. You want to have the tiniest chess server in the world?

I think the IP is logged (like all forums do) and put into the fingerprint with all the other meta data available.