Instinctively I want to say mass suffering, panic, and a huge pause button on the entire online market would obviously cause a luxury like collectible, old video games to decrease in price. But COVID-19 happened and here we are, so truly I don't know. I would guess in the short/medium term prices increase. When the market was hazier pre-Ebay, dealers were able to exploit knowledge gaps and local supply by selling things like stamps, rare books, and Beanie Babies at a premium to buyers with less info and fewer choices. Once the online market existed, more common stuff was so easy to get, and tons of stuff crashed in price.