I took their question as “new vs used”, and replied based on that. There are plenty of functional phones out there that you could use if the network still (emphasis on still) supports them, so I don’t think it’s weird to assume that someone might think “why should I buy a new feature phone instead of using my Sony Ericsson from 2000-something?”.
There’s plenty of newer used models (as recent as you want, including this year) that invalidate your weird statements.
I’ll agree that you don’t have to buy a brand new one to get modern network support, but I also don’t think there’s really much of a used market for them. In the smartphone era, they’re such a niche product that I doubt that there are many people who bought them and are now trying to sell them. I know I would rather keep it in a drawer than go through the hassle of selling it for a price a buyer would consider fair.
Alright, I’m not gonna get dragged into a game of “win the argument”, have a good one.