If you're running a place like this, you're likely to want to reduce your liability risk as much as possible, I imagine. Doubly so in as litigious a country as the USA.

My partner and I hand-fed three huge adult Capys a couple years ago, they were extremely chill and gentle. I loved them. Then I got to just sit and chill with/pet them.

The binturon was much more scary, we didn’t get to be in the room with an adult. We DID get to be in a room with two baby bearcats, which then proceeded to crawl all over and made us both cry due to how cute and curious they were. I loved them soooo much.

Maybe to prevent germs spreading to the capybara?

I doubt he is, given how gentle and chill capys tend to be, but there might be other animals in the place that the zoo can't be so sure about 🤷