A few years ago he also said that bitcoin was in bubble and people should stay away from it, by the time bitcoin was traded @ $600. Again, he made bad statement about bitcoin, I hope he will regret it someday (like Jamie Dimon did). In fact Warren Buffet admitted that he has limited understanding in techs.
https://www.cnbc.com/2017/05/06/warren-buffett-admits-he-made-a-mistake-on-google.html
So I hope he is wrong again this time