Australia

You seem to have a very high expectation of professionalism.

Trained professionals who are supposed to have skills and knowledge and experience make mistakes all the time, sometimes through ineptitude, but also through laziness.

Whether it's Doctors, lawyers, accountants, architects, any profession really. In many or most cases the client doesn't suffer real harm, or if they do the costs of litigation would be higher than the compensation.

A referral to a professional body is usually not very serious. Doctors are referred to the board for malpractice all the time.

I'm a tax consultant. We're regulated by the Tax Practitioners Board. I find it extraordinarily unlikely that they would take someone's license over a submission to the ATO that relied on false cases. Basically they only take action in cases where there is little or no doubt that the practitioner sought to intentionally mislead the tax office.

So, you personally might not think the penalties are harsh, but I can assure you that restricting someone's license to practice, whatever their profession, is a measure usually reserved for fraudulent behavior.