Tax preparation / accounting do not qualify?  Here are a few good articles on the topic even if a couple are somewhat dated:

Qualified Business Income Deduction (QBI): What It Is - NerdWallet

AICPA recommends QBI improvements (journalofaccountancy.com)

TCJA-Qualified-Business-Income-Deduction-Special-Report.pdf (thomsonreuters.com)

It's obviously a nice benefit for those who qualify.  Hopefully the current administration does not eliminate it.