Are you sure no country has approved Bitcoin? Many countries have accepted bitcoin and stayed positive on cryptocurrency. They have been using bitcoin in business transaction such as paying taxes, booking flights and ATMs. Bitcoin cannot please all people.. Its natural..
Even if the 2nd richest man have those words for bitcoin, the existence of bitcoin still depends on the people that believes in it..
That could be devastating if it will happen. It's just like bitcoin has no value at all. Having said that means you can't use bitcoin for 10 years and that's a long span of time. But I highly doubt that specially a lot of people are approved in using bitcoin and its getting popular too. Other reason is that bitcoin is internet related and our generation can't live without internet because it makes life faster and easier