For anyone that is not aware of the new standard there is a BSI white paper available here: https://www.bsigroup.com/globalassets/localfiles/en-gb/product-certification/ppe-eye-wear/en-iso-16321-white-paper-230720.pdf
If you look at the physical requirements tests, while they say that the new 'C' impact rating is equivalent to the old EN166F rating, they actually use a bigger, heavier test weight now.
The one thing that does confuse me a little though is the use case:
Might make any insurance claims tricky if they fail in use, seeing as the standard only actually applies to eyewear for occupational or educational use.