Many alts will just die off but something can easily come along that receives widespread adoption, maybe even more than Bitcoin.

I read one article where some guy predicted some sort of corporate run crypto could come along (like from a gas company, cellular company) that would allow people to pay for that service using the coin. Personally I don't see that taking off as distrust in corporations is growing. If a crypto comes along that surpasses Bitcoin, it will definitely be decentralized.