Oh. Back to resistance: Doesn’t really matter audio quality doesn’t care it’s still the same AC signal just with less amplitude

Only for ideal resistors.

Resistors are noise sources. Intentional resistors tend not to be too bad (and probably won't be heard in this situation unless you have super-high-impedance headphones, perhaps 10's of K), but unintentional resistors (eg corroded unstable metal contacts inside a plastic part) can be atrocious.

A few things to add to this:

(1) If your resistor acts even slightly like a diode then you will encounter partially rectified RF signals (more noise yay). Metal oxides between metals can do this, eg if the connector has crimped two badly-plated bits of metal together.

(2) Plasticisers in some plastics can leak out, causing corrosion on unseen internal metal parts.

(Of course linking all of this together is just conjecture, the causes of Moss' bad adaptors might be something completely different)