There's a chance that some kind of blockchain technology could underpin transactions in twenty years, but the odds that it will be anything available today are pretty close to zero. When something better comes along--and it will, this is baby stage math and technology--why on Earth would anyone accept assets in bitcoin/aeon/etc as having any value in the new scheme? These are nothing but science projects with a shelf life.
Network effects are a powerful thing. There are far better coins than bitcoin, but it remains over 50% of total crypto market cap because it got a lot of people using it before anything better could do the same. General rule of thumb is that for a competitor to unseat an incumbent technology, it needs to solve an important problem 10 times better than the incumbent. Otherwise general inertia and network effects are too difficult to overcome.
Paypal replaced the check and money order as the dominant form of payment on ebay because it was 10 times better than the alternative when used in that market. Strong adoption in that segment in turn led to strong adoption in other online marketplaces, taking market share not just from checks, but now also from credit cards (though to a lesser degree).
Paypal remains in that dominant position how many years later? Surely smart people developed better alternatives in that time, but they remain marginal players, as "10x better" has not happened in the markets paypal plays in.
But this has occurred elsewhere: Square is 10x better than regular merchant accounts or "cash only" options for food truck operators, swap-meet sellers, and independant coffee shops.
Bitcoin is 10x better for buying and selling drugs, extorting ransoms, and gambling online. Those early use cases gave it enough real activity that now it's also used heavily for wild speculation and financing pump and dump ICO's.
Hard to say if this early lead as a "payment method of last resort" will translate into success as a mainstream payment method. However, if the payment delays and processing fees can be substantially lowered, the large installed base of both users and software integration makes that "10 times better" threshhold a very high bar to clear.
Anonymity, low fees, and fast transactions are things many other cryptos are far better at compared to Bitcoin, and yet few of them have seen much use outside of speculation. As a payment method, very few are accepted hardly anywhere, even compared to bitcoin, which is also not very widely accepted for purchasing "normal things". To me that says that these advantages are not sufficient to reach that "10x" threshhold on their own.
So really, it's a race to see if the next big thing can solve an important problem 10x better than bitcoin already does, or if instead bitcoin more quickly solves its own problems sufficiently to achieve mass market acceptance. Whatever happens first will become a very durable technology.
