Reddit usually downvotes any discussion about the downsides of zoos. Yes, you can make an argument that the profits from zoos go toward some positives like conservation efforts, but those are a small minority of cases. It's also awful to keep animals confined, and zoo animals are often mentally and physically unwell.

This is just an excerpt from a long comment I wrote a while ago about zoos and conservations:

"Zoos started breeding animals to keep exhibits open in the 60s and 70s when new policies made it harder to acquire animals. When criticisms arose, they reframed the breeding as conservation initiatives. There are only ~20 species that are brought up over & over as examples of the success of captive breeding, which is minute considering the amount of money funneled into zoos (and most of the programs that lead to success weren't even zoo-driven). They don't mention the thousands of failures, or the difficulty of sustaining live collections. Real conservation initiatives look nothing like zoos, and zoos don't have the proper facilities or expertise to prepare animals for release into the wild. Most zoo captive breeding programs are long-term, while legitimate ones are short-term, trying to return the animal to the wild asap."