Think he's trying to give a cautious warning but end up going binary 1 or zero. infinity or zero. Most people who got into the market at good times in 2017 have not seen how insane the market has behaved in percentage term. Bitcoin went from $30 to zero before back then.

Another note, it looks like these days currencies rarely go to zero. last i checked the infamous bitconnect that has collapsed https://www.coingecko.com/en/price_charts/bitconnect/usd is still trading and has value

i starting to think of it like physical coins that goes out of circulation. wanna buy an old franc or roman coin, its worthless but people are trading it for its rarity; or it becomes cheap enough to be speculated again.