Brookfield Zoo actually has two current in-use maps, which I think is a great compromise. The commonly available map is a more artistic choice, but there is a minimalist map available to visitors with disabilities who may have sensory issues.
This is the current map, variations of which have been used since the 2000s. I think the most recent print version includes the name of the plaza that is empty here. The animals are pretty clear into telling you what is where, but also the paths are VERY clear and easy enough to follow, not blurring into the buildings or green areas.
Here is an older version for those who may be curious. I was considering uploading my own copy of this version to the gallery for historical reference...
This is the minamlist version, which has been adjusted a little over the years: I think a different version was in use on my visit in 2017 when we needed a copy for a disabled relative who visited with us.
I actually really love that the zoo makes multiple options available! I think more zoos would benefit from this approach. My preference is obviously the more artistic map but I could see myself using the minimalist one in certain situations.
On the opposite hand...
I've never been a big fan of Milwaukee's zoo map and it wasn't even easy to find a good one online right now. (This is pre-Adventure Africa, accurate to my visits though!) I don't feel like we need every version to include the parking lot although I can see why it would help some. The text is so tiny even on a physical map, a lot of it requires glancing at the key to figure out, and obviously the map has only the tiniest of silhouettes, and many of the enclosures aren't individually labeled. This has been the same format for maps going back to the 1970s: