101 does not (and much more does not only) require that something relate to "an articles of manufacture" to be patent-eligible, it requires it to be an invention of a "new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof"

It is quite arguable that, assuming cars exist, a "red car" is, to the extent that it is new not useful, and to the extent that it is useful not new, and therefore patent ineligible.

So, no, while I agree that your analogy may be relevant, I don't think it illustrates that the Supreme Court is confusing patent eligibility with patentability. I think you are reading patent eligibility far too broadly.

> 102 is novelty

Its true that 102 has specific novelty requirements on top of the patent-eligibility requirements in 101, but that doesn't mean that things don't need to be "new and useful" under Section 101 before one even needs to consider whether they meet the specific novelty rules in Section 102.