If paypal is sending 1099 KS to every user, why is cash app not, and only sending to business accounts and not personal accounts? How are they determining what are goods?

How are these payment apps determining what transactions are for goods and services,  and what transactions are for gifts, borrowing and repaying friends or relatives? And the majority of people do not save and record receipts for selling used items. It seems like this may turn into a sticky situation.