Does someone else spend time on it (on behalf of the owner)?

You'll find a spectrum of opinions on this.  Some folks take the position that just about anything qualifies as a trade or business.  The IRS came up with a safe harbor described here:

https://www.journalofaccountancy.com/news/2019/sep/rental-real-estate-safe-harbor-qbi-deduction-2019...

I'm somewhere in between.  Probably one property with little involvement doesn't reach the level of trade or business.