Don't worry. According to Mike Hearn Bitcoin can survive just fine with 4 or 6 (forgot which) copies of the blockchain worldwide.
Is he right or wrong about that?
Via what methodology would we test that hypothesis before arriving at a conclusion about its validity?
He's 100% right about that. Bitcoin could probably survive with a single blockchain much like the federal reserve maintains one source of truth.
The statement is enlightening because it demonstrates the stark differences of Bitcoin in our world that different people have. Like you and I for instance from everything I can see.
If one sees tainting as a good an necessary thing, and understands the communications optimizations which are possible between large and well funded business entities, then a small integer number of existing blockchains makes all the sense in the world.