As someone who speaks both art and computers, I can assure you that it's at least as rigorous and significant as, say, the startup community's language. The problem with trying to make a counterexample of hard science is that you're opening up to excluding every subject that isn't hard science to the same criticism.

The purpose of the language of art theory and criticism isn't to communicate objective truth, because it's subjective truth. But just because a truth is subjective does not make it less real, or less meaningful. Generally, we are limited to the subjective reality of our perceptions. Art theory is the study of perceptions, and a great deal of modern art is more or less experimenting with perception itself. Knocking it as "bollocks" because it's not expressed in formal logic or mathematics is both subjective and non-rigorous. Or, as the Dude would say, "That's just, like, your opinion, man." If you don't understand the language, that's fine, and if you don't care to understand it, that's fine too, but calling it bollocks without understanding or caring to understand it is itself bollocks.

If you start digging around in philosophy, there's a strong argument within phenomenology that physics itself is subjective. Rigorous language doesn't mean the subject of the language is objective. Godel demonstrated the limits of language against objective nature in his incompleteness theorem as well (basically, Godel proved that, within any system, there are statements that are true that cannot be proven). But I digress.