I never understood this attitude.

IF (and only if) your help would very likely be useful and you know how to approach the person, then, why not?

As for the software angle, Clippy was indeed dumb and rarely offered useful help (partially because, as one of the comments above states, some boss forced engineers to replace a good algorithm with a more business suitable algorithm). But in general, I subscribe to the idea that software should be less interactive and guess more (and let you correct it, if the guesses were wrong).