I think it comes down to how you define "available bitcoin supply" ...

if you define this as all 21 million BTC.. then.. nope, not gonna happen...
if you define this as all BTC currently mined.. then again, nope...

if you define this as "total sum of all BTC currently on exchanges" .. then.. well.. a consortium of billionaires could theoretically have the ready funds to snatch that up...  I highly doubt there are more than a million BTC on exchanges at any one time.  The majority of coins being either not yet mined, lost, or in the hands of HODLers.

Same thing if you change the definition to coins available on various OTC platforms...

OR.. this could be a total marketing piece and they are just talking crap.