and btw, tcp/ip v4 has the fatal flaw too, namely extremely inadequate addressing space, known since 30 years ago. you know what? we learned to live with that instead of replacing it with a superior tech. because expensive to replace everything. with every passing day, it is less and less likely that bitcoin will ever be replaced.
Are you suggesting that Crypto 2.0 will be IPv6? Sure.
ipv6 is the "soft fork" of ipv4, superior, exists for many years, and still only like 3% use it. if bitcoin is ever hard-forked in a way that renders all existing infrastructure obsolete (and that's what an "altcoin successor" can be seen as), the resistance will be huge, and the new fork/altcoin will die quick death because it will be unsupported by any invested parties.
Any evolution in bitcoin will happen gradually, with changed behavior co-existing with the old one, just like ipv4 coexists with v6 today.
And no, bitcoin is not in alpha. You can send a million dollars worth of bitcoin to Uruguay today and with a 99.99(alot of nines)% chance it will be there in an hour. Unlike any existing banking system, where manual labour will be involved often to see your transaction goes through all the routing hoops successfully.