There will be tons of such appliances from the mid 20th century and onwards available on craigslist, flea markets, probably even ebay amaon et al. for quite a while.
Joe Middle-class Consumer does not want to buy their appliances from Craigslist, flea markets, etc. The mass market audience for appliances want to buy new in a store, with a warranty, etc.
I fully expect to see a gradual boiling of the frog. First it will be free features and benefits tied to an online account, then it will be new features that are only part of a subscription plan, and once they have critical mass, killing the free tier or making it near worthless.
Sure there might be a market for used devices, but again, it will be the minority. The rest of the marketplace will be screwed.
There will be tons of such appliances from the mid 20th century and onwards available on craigslist, flea markets, probably even ebay amaon et al. for quite a while.