I see at least three problems with your criticism:

1. Orwell doesn't provide any useful guidelines on when the exceptions to his rules should apply. He only says you shouldn't use them when it would make you sound "outright barbarous." But this makes these rules useless as advice, since the exceptions are supposed to be guided by aesthetic feeling -- and those whose feeling is refined enough ipso facto already know what to do even without Orwell.

2. The second LL article cites a result that the use of passives in Orwell's essay is in fact well above the average found in a large sample of English prose. So whatever exeptions to his rules he has in mind, this necesarily implies that he breaks his own advice. There is no reasonable interpretaton of his admonition to avoid passives, whatever caveats and exceptions are attached to it, that would permit writing a whole essay with such an exceptionally high rate of passives.

3. One sample of old text is very weak evidence of the average quality of old writing. Especially considering that it's from a highly non-representative source. (By which I mean a high-budget collaborative translation by top-rate English stylists, which has also survived popularity competition with other Biblical translations.)