It hasn't always been the rule. The threshold used to be 200 transactions or $20,000 transferred through a business account on a payment processing app. Now, that threshold has been dropped to $600. Remember all that hoopla in the news about how the administration was going to start looking into everybody's bank account that has over $600 in it? That was the spin the media put into it so that the talking heads wouldn't be lying when they said that wasn't true. What IS true is they're using that $600 threshold to squeeze every last tax dollar they can out of as many people as they can. This time, it'll hurt the little guys the most. Larger businesses have always been above that previous threshold, so it was never really a problem.
Keep in mind that this is not about goods sold at all, it is about money transferred through third party payment processing companies/apps. So, eBay/PayPal/Venmo/CashApp/whomever will send you a 1099 regardless of what the items were that you sold and whether or not you sold them at a loss or made a huge profit. It's not about those details. All they did was process more than $600 of payments to you and that's what triggers the 1099. So far, the only recourse is to make sure that people sending you money through those apps is doing it as "Friends and Family", that'll avoid the auto-1099. Obviously eBay doesn't operate like that, so they're the exception to the F&F loophole. It's now up to you to prove to the IRS that you sold those items at a loss.
Can one of you tax pros on here tell me how I'm supposed to do that with items that I've had either in my possession or my family's possession for over 40 years whose original sale price cannot be found on the internet? Even if I did know the original sale price of said item, do I get to adjust it for inflation and put that on my taxes somewhere/somehow?
So far, the only way around this automatic-sending-of-the-1099 situation for online payment processing is to use Zelle. They're the only ones not reporting anything to the IRS. They leave the onus on the end user, as it should be. Most banks in the US use Zelle as their preferred payment processing app, so check it out with your own bank. They do have limits on the amount that can be transferred, but it varies with each bank. Some are daily limits, some are weekly. Call your bank to find out and if it works for you, great! As for selling pinball machines, though, cash on glass is most likely going to be the only way forward. At least until November or a new administration...