That's just not true. Lots of people buy used solar panels to do cheaper DIY installs.

Solar panels do degrade, but its not anywhere near "rapid". Go look at the lengths of warranties on panels these days

Sorry- yes there’s a used market, but the pricing is essentially handling and refurb cost. used panels are sold by the pallet for the price of a new single panel. Vastly different from a used car industry.

That being said… I might buy a pallet