I feel like a few people have their causal ordering mixed up here. They expect some sort of "crash" followed by a drop in prices, when in reality it is usually a price drop that leads to a crash in the market. Right now the pinball market is getting healthier and we are starting to see more accurate pricing based on effective demand. Companies like stern are producing the number of machines at price points that they know consumers are willing to pay. Right now their costs of operations are high because they are matching supply to that demand. However, many are taking steps to increase that demand through marketing. We're even seeing companies like frontgate and sharper image who appeal to high end luxury consumers, starting to sell pinball machines. Which makes sense, since most who were teens playing in arcades during the 90s are in their 30s and starting to be able to pay NIB prices, which were always relatively high. This allows companies like stern to increase the scale of their business and offer more supply with increasing demand. It also provides room for boutique companies like spooky to offer cheaper alternatives.

As more companies emerge to compete for a share of the pie, they will be willing to settle for lower profits. Eventually the market will become saturated and no longer profitable so manufactures will be scared away. After a few years of no new products, high end consumers will walk away as well, and overall inventories will fall. The few collectors still left will be willing to pay absurd prices for the "rare" ones, and the vast majority will care less about the pinball world. This can all be avoided as long as supply is matched to demand, which will periodically rise and fall, and as long as companies don't scale too big that they aren't able to weather the storm during downturns.

In the next couple of years I think we can expect to see an increase in supply with rising demand and a range of nib offerings from $5k-$10k. In terms of collectibility, the ones that offer something unique or appeal to a particular subgroup for nostalgic reasons will demand higher prices, while others that cannot compete with the newer technologies will simply become inferior goods worth the price of the scrap materials they're made of. Like all hobbies, have fun, buy what you enjoy and can afford, but realize there are probably better ways to invest your money if your goal is to turn a profit.