I mean it's fairly straightforward when considering if "uncontrolled outdoor access" has dangers and harms to the cats

Uncontrolled outdoor access allows these natural behaviors, but it also poses a number of significant health and welfare risks, and the overall benefits of the performance of these behaviors is unknown.

But if you're not willing to take their word for it, there's other people talking about those dangers too

https://www.orangecountync.gov/1331/Safety-concerns-for-free-roaming-cats

https://www.avma.org/resources-tools/avma-policies/free-roaming-owned-cats

https://stories.tamu.edu/news/2023/10/19/how-free-roaming-cats-impact-wildlife-disease-transmission/

And so on and so on.