You clearly don't

Draw an extrapolation. I've done this, and if 2 billion USD were suddenly dumped (say Tether value is 0) then the price would probably decrease by about 10%.
Anyone claiming 30% or higher is a FUDster, trying to get cheap coins or blow something out of proportion.
Seems to be working, sadly.
We've seen in the last 3 weeks that 15-20 Million $ are enough to move the market by 7-10%. Look at the past "pumps" at 10k$ and the needed volume.
Dumping 2 Billion would crash BTC to 3 digits...