IMO eBay is less scammy.

I've been using it to buy car parts and it is SO MUCH better than dealing with junkyards (LKQ/Car-Parts websites suck!) and everything that I've got so far including parts from Latvia and Germany have been genuine.

eBay too is full of knock-off trash from China but you can easily tell those apart from a real listing most of the time with reviews being unique per listing/seller. And eBay allows for local pickups too!

eBay is better as each seller gets a distinct listing Amazon letting sellers just kinda take over listings is a huge problem and has led to many scams like this and more commonly review scams where they sees the listing with positive reviews for a legit cheap product but swap it out for whatever their money grab is.

I have always had very good experiences with eBay. Several times I’ve been screwed on Amazon. With eBay I can also add a lot of filters to my search which I like. I can immediately exclude items shipped directly from China. Or search for something within 100km so I know I can just go pick it up. eBay has just been so much better from my experience.

Amazon is a more expensive AliExpress.

Definitely or worse. I use Amazon as a last resort. eBay is first choice for cheap stuff. For expensive stuff I tend to go for bricks and mortar stores.

eBay has miraculously become more trustworthy than Amazon for certain products

I have never had a bad experience on Ebay. Paypal taking my money hostage is another story.