Old ideas die hard; I'm having a funeral.
At my peril, I'll argue ever so gently, going not to the Vatican's site, but to the Swiss Guard's site.
The url unfortunately doesn't change from page to page, so you'll have to browse through the site.
1. Choose your language.
2. First page says, "Modern, well-educated Swiss young men wear the traditional Renaissance uniform."
3. Click on "Guard" at the left, then on "Command," then on "Uniform." Be sure to scroll down to read all three paragraphs, which confirm what's been previously posted.
[schweizergarde.org] site no lonmger exists
https://hallowedground.wordpress.com/2008/08/12/swiss-guards/
The story about Michelangelo's designing the uniforms, although now disbelieved, was widely disseminated. No documents attest to his hand in the design, so perhaps this is one of the oldest continuing urban legends. (I just have to say, though, the lack of documentation doesn't prove it false.)
The 1958 (not a typo) World Book Encylopedia notes under a color picture of the guard, "Their colorful costume was designed by Michelangelo, in the 1500's." (Their comma.)
Compton's 1993 encyclopedia states in Vol. 18, p. 110, "Members of the Swiss Guard in the Vatican still wear the traditional uniforms and helmets designed by Michelangelo." The front matter bears the seal of the University of Chicago and says it is "...published with the Editorial Advice of the Faculties of the University of Chicago." Scholars ferret out some mistakes and perpetrate others. We can hope the Vatican and the Swiss Guard have straightened this one out for us.
RIP