--edit: The suggestion that 20MB is to small and is just a first step toward 'scalability':
It certainly calls to attention the feeling that the gavincoin fork is the proverbail 'camel's nose in the tent' and most of the adherents have no intention of stopping there. As I said, stopping there would be pointless.
The end-game is a vastly larger block size so it is not the slightest bit irrational to consider the choice as being between a lite-weight and defensible (and hopefully decentralized) system and one which is very far from this.
The end game doesn't stop there because we cannot foresee the future. Perhaps there is never any need for increasing the block size past 20MB, perhaps we use sidechains in the future, perhaps we keep increasing the block size because
future mesh networks can sufficiently handle larger blocks in a decentralized manner, and perhaps a new innovative solution is created to solve the problem.
It's really piss-poor design to build a defensible subsystem on top of a non-defensible foundation.
The whole point of sidechains is that they can rely on a small independant core (native Bitcoin) to provide a plethora of tunned solutions. These solutions can address a whole host of needs, some of them being mutually exclusive. This will allow protection for native Bitcoin by allowing it to remain tight and basically static (not needing to encur risky and objectionable changes.)
The fact that native Bitcoin is utterly critical to the value base of various autonomous sidechain efforts could provoke a need to support native Bitcoin regardless of the failure of simplistic economics to do so. Especially if that is part of the basic design or used to solicit use of a particular sidechain which it would in my case at least.
There isn't some secret conspiracy with an end goal of centralization and I doubt Gavin wants that either.
Yes, I'm sure that for the most part it is and expression of ignorance by those who have no real experiance with system design.