I can totally understand your frustration and empathize with your situation. Coincidentally I can actually speak from personal experience because twice in the past six months, I have listed and sold items on a platform to two different buyers neither of whom had any feedback whatsoever.
Yes, there is “protection” for sellers on PayPal but it is also true that there are known scams that do occur on the platform. I do consulting and I have one very large customer who does millions of dollars on platforms like Amazon and eBay and eBay in particular is known to have a close working relationship with PayPal, which they at one time owned, of course. He was unequivocal in his advice to NOT sell to a buyer with zero feedback.
in my case, I was actually able to have a conversation with both prospective buyers and because I have an extremely high seller rating, each buyer was totally comfortable in sending me payment via Zelle or PayPal friends and family.. I had enough confidence in the buyer once I spoke with him to accept a small deposit, but requested respectfully that I be sent the full payment in advance of shipping, which I agreed to cover myself. Both buyers clearly had the confidence in me as a seller to pay via Zelle or Venmo or AppleCash.. so for my part, it had nothing to do with taxes or the IRS or anything. I’m simply aware of the fact that scams occur that are perpetrated by buyers even on platforms like PayPal that offer buyer protection. It has been known to happen so I understand both sides.
So don’t take it personally, but consider it akin to “paying your dues” until such time as you have at least one or two pieces of positive feedback.