@Carl Further on in the article I cited, it says this:
In its final regulations on the pass-through deduction [emphasis added], the IRS discusses how to determine if a rental activity qualifies as a business. It says that "taxpayers should consider the appropriateness of treating a rental activity as a trade or business…where the taxpayer does not comply with the information return filing requirements." Information returns means filing Form 1099-NEC. In other words, it may not be appropriate to treat a rental activity as a business if a landlord does not file all required Forms 1099-NEC.
This is something the IRS has never said before. So now we know: Landlords should be filing 1099s. Failure to do so is a mark against you if the IRS ever questions whether your rental activity is a business.
