There are a number of professions in the US where yes, this is somewhat regulated. I can think of a few:
1. Medical doctors
2. Certified Public Accountants
3. Lawyers
4. Professional Engineers
5. Realtors
Many other professions and certifying agencies will claim that a certification is necessary to practice, and that you should pay them for the privilege, but these are some of the few that are legally protected.
You need a "Professional Engineer" certificate from the NSPE to sign off on certain documents. But note that these certain documents are only used in certain fields, like civil engineering. This certification is not required to be (or to claim to be) a software engineer, electronics engineer, mechanical engineer, product engineer, chemical engineer, etc. For example, I've taken many engineering courses, I have a bachelor's of science in engineering degree, and I practice engineering day-to-day without being a professional engineer. In college, perhaps 5% of my graduating class took the PE exam? And now, few of my coworkers, customers, or suppliers are professional engineers - The two individuals that I can think of transferred into the domain out of civil engineering.
The electronics engineer in the article mistakenly stumbled into the territory of civil engineers who are very, very protective of their licensure, and they overreacted IMO. I don't dispute that if he'd claimed to be an NSPE-licensed Professional Engineer, and signed off on documents which are legally required to be approved by a PE, that he'd be deserving of the punishments associated with this fraud (which are much steeper than $500). But the NSPE does not own the generic term "engineer".