I'm sure they aren't saving ONLY in crypto. Millennials are smart enough to know their dough needs to be divided. People are getting richer younger, and new avenues for investment are always in demand.
i really wouldn't be surprised if many are entirely all in. one thing young people usually have a shortage of is long term strategy.
Do you think that the pension system will exist in next 30-50 years from now, or people will be forced to work while they live? Why would anyone be crazy if invest in cryptocurrency then in a pension fund, trust more to governments then crypto?
It is true that that crypto is just 9 years old, but for anyone who invest less then 50$ in BTC back in 2010/2011 and if he kept coins untill today, we talk about millions $ of profit. That means these people are retired today, and enjoy without stress and fear for their future. I'd rather risk my money in crypto for next 10-15 years, then trust that money to my government - they will fall much sooner then BTC.
i wouldn't be surprised if there are no government supplied pensions in a few decades. they're all effectively ponzis and lifespans, or rather expected retirements, are too long to sustain them.
as for the 9 year old thing, the thing you read anywhere regarding investments is the old past performance is no guarantee of future performance.