I was able to get ~33% off my Altima in 2011 and ~20% off my Ody in 2013. From what I've seen getting under sticker now is nearly impossible, though I didn't verify that myself due to the other 2 factors.
With those negotiating skills, you may be right. For the rest of us normies, new has more value than used right now (for most vehicles).
Only certain models.
It's definitely more than a few. I'm sure there are models that doesn't apply to, but I haven't seen any myself.