I am pretty sure it is more than that like 1.5-2 billions that are now in the pockets of topnotch hackers or huge whale group of scammers or anyone related to any syndicate that has a huge influence on the financial industry. But ICO barely scam anyone anymore so I hope the next batches of upcoming exchanges have learned from those reports to tighten up their security.
1 billion probably just means a few hundred million at the end of the day, thanks to all the ways to discover tainted crypto plus of course how some private blockchains can detect and freeze transactions in agreement with exchanges. Was not some of the stolen funds from NANO for example done like this? They saw that it was going to be exchanged at shapeshift and SS just froze and confiscated those funds and returned to exchanges?