Pants — "is it" or "are they"?

It's a matter of the signifier versus the signified. The question being asked is, "why is the word pants plural?" It could as easily have been, "why do we need more than one pant?"

In the first case, since the subject for discussion is a single word, the singular form is correct (if a little odd-sounding at first). In the second, the subject is the article itself, so the option is to pluralize everything or propose a hypothetical singular.

Pants is always plural. Therefore it's "my pants are ripped" or "I don't like them". It's the same with other plural nouns, like binoculars, glasses, etc.

One says "are your glasses alright", not "is your glasses alright", so it makes sense to assume that they are plural, not singular nouns.