The Google-owned company said it will “highlight” more videos with authoritative sources when a user searches for specific health topics. It will also add “information panels” that display a link to credible sources recommended by the National Academy of Medicine. The tool’s effectiveness will be based on the viewers’ willingness to click on it, however. Experts have repeatedly doubted similar tools the company added to election videos last year.

Source: YouTube labeling some health videos amid misinformation backlash

Youtube has not provided a definition of “authoritative”. The way this may go is to highlight content affiliated with “organizations”, and then to content based on credentials (MD, PhD, typically).

Bertrand Russell remarked that a fact is true regardless of who says it. But in a credential-based world, facts are true based on the credential, which is an appeal to authority argument. Such arguments do not mean the information is true – arguments are true based on facts and logic, not on credentials.

Longer term, this might mean Youtube will bias watching videos affiliated with persons having MD and PhD (and maybe JD) degrees.

This could eventually apply to other topics. I am retired computer engineer (BSCS, MS software engineering, MBA, plus much additional graduate course work in informatics and computer security). But I do not have a PhD.

If I produce video content on a controversial subject in computer security, will my video be “de-legitimatized” because I do not have a PhD?

We do not know and Youtube is not yet saying.