Although I am not against the 1MB block size limit being raised it seems to me that the entire point of "decentralisation" seems to have escaped the Bitcoin project (the core devs at least mostly seem to be completely against having other blockchains).

I certainly understand that the Bitcoin Foundation is going to have that opinion (for financial reasons) and I can understand a lot of people heavily invested in Bitcoin (such as the Winklevoss twins) also having that opinion.

But any "rational" person would surely think that having other blockchains (with different code and proofs) cannot be a *bad* thing as it alleviates the "one point of weakness" we will otherwise always have.

I don't see how "one blockchain" is ever going to service the needs of everyone (without requiring a ridiculous amount of space and without having near instant confirmations) so IMO it is simply inevitable that we are going to need many.