But isn't that the meaning of 'It depends', that it depends on other factors?
The price (in money) that people are willing to pay for something is of course not the only factor in deciding how good something is (to them), but surely it can be considered one of the factors?
For example, I just bought a new phone, the model up on my old one, which I contrived to break. I could have bought the old one again, as I liked it, or I could spend about $100 AUD more for the model up on that.
I decided to spend the $100 more, hoping it would get me a better built phone (it did). For the quality increase would I have spent $200 more? Perhaps. $300, possibly not. $400 more? No.
So while my new phone is better than the old one, it's only worth a certain amount to me.
So basically, I don't believe it's at all on a par with your comparisons, price is certainly not always an indicator of merit, but it can be. It depends.
To take another example, in Australia, Lagavulin (or Laphroaig if you prefer) is quite expensive, but it's certainly worth it to me. Double the price, and it isn't, except maybe on special occasions or something.
Cheers
Garry