There's nothing stopping a manufacturer from developing a good track record with an Android phone, but so far most haven't. Developing such a reputation could be a strong competitive advantage for someone making Android phones.
Apple can do that with the iPhone and Google can do it with their Nexus models probably because they don't release a bazillion different phone models in a year (like HTC/Motorola/etc...).
Take for example CyanogenMod - the guys involved in the project don't get paid by any of the manufacturers, but they are able to build ROMs that can run on a host of devices while providing a consistent stock-Android user experience. How is that for being open.
List of devices with nightly CM7 (Gingerbread) builds: http://mirror.teamdouche.net/?type=nightly
Sure, executing five command line operations and rooting your phone is more of a pain in the ass than doing nothing. But if I was stuck using a Cliq XT as my daily phone (certainly would never happen, but let's just suppose), then I really would be sitting there saying, in earnest and without irony, "Well, luckily Android is 'open' and I can fix this."
But I'm not actually sure if rooting and upgrading your Cliq XT is really that easy, or if Gruber is just taking Andy Rubin's tweet out of context to make today's snarky little if-technologically-handicapped-people-can't-understand-it-then-it-sucks point.
This post comes across as a fairly passive-aggressive attack, or a snarky child. I don't know why people rate Gruber's posts. I haven't found his analysis to be particularly insightful. He is usually clear in communicating his feelings about an issue and for that I'd give him credit. But whats the point in reading a clearly communicated thought if its effectively, "I dislike Android, and I intend to bad mouth anything related to Android at any possible opportunity."