The term "safe harbor" is used to describe when something is a lower bar to reach, but that isn't the requirement. That's the point of offering a safe harbor qualification.

"If an enterprise fails to satisfy the requirements of this safe harbor, it may be treated as a trade or business for purposes of section 199A if the enterprise otherwise meets the definition of trade or business in § 1.199A-1(b)(14)."

From: https://www.irs.gov/pub/irs-drop/rp-19-38.pdf

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