[actuary]

Actuarial credentials aren't licenses. In the United States, they confer no privileges aside from the ability to sign a particular statement on the condition of a company's loss reserves. This is something that few actuaries will ever need to do.

Actuarial credentials are instead a market-based signaling mechanism, akin to a specialized technical degree. All signaling mechanisms are imperfectly correlated to whatever it is they're signaling for, but in my own experience, it's usually a good bet that an actuary who holds a credential will be more capable than one who doesn't. The market agrees and pays credentialed actuaries a premium. If credentials stopped being an excellent predictor of ability, there would be nothing stopping the market from disfavoring them. Note that there's one highly successful insurance company (Progressive) that has made this call and hires very few actuaries. Most companies wouldn't be able to follow their operating model, but that's a different conversation.

And if the actuarial societies and insurance companies are trying to preserve scarcity of actuarial credentials, they're doing a poor job of it. The test-taking process continue to be well-supported by insurance companies. Junior actuaries typically have all exam expenses paid and are given an additional 25 to 30 extra days off per year to study for exams. The number of credentialed actuaries has exploded (I think more than doubled) in the past decade. There are no quotas and no economic barriers after you get your first job.

I do like your comparison with Michelin-star restaurants. Michelin stars are a signifier of quality. The letters after my name are too.