Not as easy as you'd think to prove something is a fake, especially niche items like mics, you say it's fake, sller says it's real, what do you expect eBay to do, phone Neumann and request a formal appraisal? But it's not just that, eBay are also aware that if they simply removed every reported fake it would be chaos, every disgruntled customer, every scammer, and every dodgy dealer who'd happily report their competitors to eBay or similar for selling 'fakes' just to get them off the market, would be at it 24/7. I think we just have to be proportionate in our expectations of eBay or shop elsewhere