I would tend to agree with this.  Like any type of investing, no one actually knows the future of markets or they'd be even richer than they already are.  Yes, some markets track upwards over time like global index funds, and Bitcoin might do the same.  However, I'm unsure if some of the predicted future values can actually be realised.  People predicting it'll rise to a million come 2030, MMmm I'm not sure.  Although Bitcoin is the daddy of crypto at present, it doesn't necessarily follow it'll stay that way.  And, if those gains come to fruition, unless the average investor gets in very soon, Bitcoin will surely become the preserve of the rich due to the values it'll be trading at.  At $1,000,000, an investment of $10,000 would get you 0.01 and for your investment to double Bitcoin would then need to realise $2,000,000.  Yes there would still be dips, however if it reaches those heights even in the dips it would still be trading at hundreds of thousands (unless it practically crashed) so would still be out of reach to most in terms of holding a decent % of a coin.