In the article, he predicted that the network will come to an end in 2061. But not before the price would reach as high as $6,000,000.
Small correction: I read that in 2061 the price will reach 6 million, and in 2100 the whales will shut the network down.
Do you think this is possible?
Possible, yes. Likely, no.
First I don't think Bitcoin will ever reach a value of more than a million. My personal prediction would be between 0,5 and two times the current Gold market cap, i.e. prices of 250000 to 800-900000. A million would surprise me, even if it doesn't seem far away. (But definitively it can go higher than now.) The reason is for me that this would only happen in two cases:
1) Bitcoin becomes the "one and only" world currency. (Won't happen for me. Traditional fiat has advantages, and altcoins will always exist, even if they aren't likely to challenge Bitcoin's leadership.)
2) Bitcoin doesn't become the "one and only" world currency, but "absorbs" capital from other markets. This can in my opinion only happen temporarily (because otherwise, "real world" assets would become undervalued), and won't be enough for $6M.
A consequence is that transaction fees on the main chain won't exceed "a couple of hundred USD", maybe 1000 in extreme cases. In the case of a $250K-1M Bitcoin most of the time they will be between $10 and $200 - thus not that much higher than at the end of 2017 (but definitively too high for a coffee, so LN will thrive).
Second, the scenario of sidechains, "wrapped" Bitcoins and Lightning as the places where the value transactions are taking place mostly is definitively one I have in mind too. But if the tx fees stay acceptable like I estimated above, it will be always interesting to transact on the main chain, as all other cases have security trade-offs.
Now let's speculate if the main network shuts down, what will give Bitcoin its value then? My estimation is that it would be extremely difficult, if not impossible, to ensure a "peg" between the different Bitcoin chains.
These chains will likely have some differences with respect to security, decentralization and functions, and so there will be a lot of speculation against the peg. First that could be slight fluctuations, but eventually I guess there will be a successful attack on the peg of one of the chains or "wrapped tokens", and then the whole rest of the system will slowly implode, because the "reference chain" isn't there anymore (no 2-way peg is possible).
PS: If the "mainchainless" scenario was possible, this would mean that one-way pegs would work, and we could solve all scalability problems instantly starting lots of chains with Counterparty (XCP)-like, Proof-of-Burn-backed bitcoin tokens. But you can already see, observing the
price of Counterparty, that the scenario doesn't work that well - otherwise the XCP/BTC price should be stable.