[unavoidable]

Passive voice is one of those things that really irks people for some reason, mostly because their grammar school teacher taught them so. It has a lot of legitimate uses, but the knee-jerk reaction it invokes in people is bizarre.

For instance, there are many cases where one would want to de-emphasize the subject, or cases where the tone should be "passive" in the sense opposite from "aggressive". If you are arguing with someone because you think they are wrong but don't want to put blame, you may want to say "It was wrong to do that" instead of "You were wrong to do that".

Another use of passive voice is for a certain dark style and more mysterious tone. A good example of this is "It was the best of times. It was the worst of times..."

[schoen]

None of the examples with "It was" are grammatically passive, though.

It's striking to check out section 3 of the Pullum paper ("Fear and Loathing of the English Passive") mentioned upthread by bshimmin. Pullum gives 22 (!) examples of people criticizing texts as being "passive" when they aren't.

Edit: Pullum mentions a purported "passive style" (which, if it really exists, among other things avoids directly mentioning individual human beings' responsibility for things that happen) distinct from the "passive voice", which might be part of what you're referring to here. But "it was..." isn't a passive-voice construction.

[trumbitta2]

> "It was wrong to do that" instead of "You were wrong to do that"

Technically true, because it's passive. But still, you'd be using "It was wrong to do that" because it becomes impersonal, more than passive.

[unavoidable]

The example doesn't really change.

> "The code was broken" instead of "You broke the code" serves the same function.

[DanBC]

What's the passive version of "you were wrong to do that"?