covid supply problems meaning new things got more expensive added to extra cash spent on stuff (esp in US) pushed prices up a chunk - then I think there's this thing that happens where there's more people flipping gear, and then the way reverb works means there's a self supporting bubble - it's less like eBay telling you the actual market value in completed sales... if you owned a unobtainium ubermojofx super tubescreamer then you and other ubermojofx owners have zero impetus to drop your price...
and then it becomes relative - if a 3leaf Proton becomes worth £500, why wouldn't a Musitronics pedal asking price go from £300 to £450?
it's all crazy. Mind you I am interested in what has gone up in price ten times!