Yes, you should be concerned and should be cross-listing onto other sites as fast as possible.
There's a lot of folks around here who will insist nothing's wrong and will brush off the current state of eBay as completely normal despite people who are just starting to cross-list to Mercari/Poshmark suddenly having better sales with less active listings while accounts with thousands of listings on eBay are receiving repeated "no sales" days.
I am hoping the third quarter reports are so terrible that eBay is forced to change management because this site isn't going to survive at it's current rate. eBay is bowing it's head to Poshmark and Amazon and practically asking for them to take it.
