The word "new" is itself obsolete

We keep using it to describe things that are fundamentally just re-combinations of what already exists, and we've been conditioned to conflate novelty with innovation when they are diametrically opposed concepts.

Exactly. Everything new has already been described.

I have to push back on this entirely, and I think it's worth being pedantic about why because otherwise we're just performing a rhetorical trick rather than making a point. The argument relies on a temporal category error: you can only call something "new" at the moment its existence intersects with an observer's prior knowledge. Before that intersection, the object exists in a state of novelty-potential — it is new by definition because there was no previous reference frame to compare against. So if we applied your logic strictly, the word would be obsolete before anyone could say "this is new," which means you can't use the observation to invalidate the word itself without being self-refuting.

Additionally, I suspect what you actually mean isn't that the semantic unit of novelty has been exhausted (which is a bold metaphysical claim), but rather that our cultural systems for signaling freshness have become overdetermined and therefore less informative at the margins — i.e., "new" as a marketing tag in 2024 conveys very little because it competes with an infinite set of competing tags, not because the concept of novelty has been depleted. That's a critique of advertising literacy, not linguistics.

But even grant