Do I sell my current gpu?

I have just bought a XFX 9060XT from newegg for $470. I had not even realized the price was up due to the ai shortages. But I got curious and now I’m looking at ebay and I’m finding graphics cards wayyyyy better than my current one for much cheaper.

I’m talking about things like a 9070xt being cheaper on eBay, and really crazy enough a 4080 super and a 5080 all being cheaper.

I’ve seen 5080s and 4080 supers go for around 400 dollars. That’s insane right?

I would think these are scams but there are multiple listings. I feel really bad for paying so much extra for my gpu and I’m thinking of selling my old GTX 1660 and current 9060xt for a 5080 or 4080 super. Are these deals real?