21 years of "Bubble burst" predictions refresher course. Yes, this actual thread is listed back in 2011.
2012:
https://pinside.com/pinball/forum/topic/pinball-price-bubble-think-it-cant-happen-think-again
2013:
https://pinside.com/pinball/forum/topic/pinball-price-bubble-will-pop
2014:
https://pinside.com/pinball/forum/topic/this-is-not-a-rebirth-of-pinball-its-a-bubble
2015:
https://pinside.com/pinball/forum/topic/we-all-want-the-ass-to-drop-out-of-pinball
2016:
https://pinside.com/pinball/forum/topic/when-will-the-stern-bubble-burst
2017:
https://pinside.com/pinball/forum/topic/are-we-in-a-pinball-bubble
2018:
https://pinside.com/pinball/forum/topic/why-i-feel-pinball-prices-are-going-to-plummet
2019:
https://pinside.com/pinball/forum/topic/will-pinball-prices-come-down-
2020:
https://pinside.com/pinball/forum/topic/prices-dropping-
2021 (this year has been a fuggin BANNER YEAR for price bubble threads...maybe it's something in the vaccines):
https://pinside.com/pinball/forum/topic/pinball-pricing-bubble-due-to-covid-one-nine
https://pinside.com/pinball/forum/topic/similarities-with-pinball-market-amp-the-2008-housing-crash
https://pinside.com/pinball/forum/topic/next-pinball-depression-
https://pinside.com/pinball/forum/topic/pingreed-is-a-cancer-is-there-a-cure
https://pinside.com/pinball/forum/topic/prices-of-pinball-machines-today#post-6229413
https://pinside.com/pinball/forum/topic/pinflation-or-inflation
https://pinside.com/pinball/forum/topic/price-gouging
https://pinside.com/pinball/forum/topic/f-you-stern-and-your-price-increases
https://pinside.com/pinball/forum/topic/are-pinballs-the-beanie-baby-craze-of-the-2020s
https://pinside.com/pinball/forum/topic/we-have-jumped-the-shark