This doesn’t affect personal taxes.
Again, this does not change personal taxes.
Now, folks are on the hook for self-reporting. Previously, the thresholds were $20,000 and 200 transactions, which were maybe too lenient. Had lawmakers just halved the threshold to $10,000, I don't think most people would care. The $600 is too low, e.g. guitars easily fetch a grand, and Leica M bodies are easily over that.
Also, what are Nancy Pelosi's stock gains compared to any folks that might have been not reporting their illicit <$20k income?
This is basically the separation that sole proprietorships have to go through. Stuff that is exclusively used for your business is deductible, anything for personal use isn't.
I think you're working from a different set of assumptions than GP. They were specifically contending that exclusive expenses could not be deducted, even if the overall net value of transactions is negative (because it's not a business, but just a partial recovery of hobby expenditures.)