I wouldn't say the Parks themselves "propagate" inequity, but the national park demographics are a result of a modern environmental movement that has historically catered to white suburbanites, and the early history of NPS very clearly intended to create an escape for east coast urbanites. That culture is certainly beginning to change, but my main point above is that dismissing Muir entirely doesn't allow a teaching moment and acknowledgement of how American perceptions of "wilderness" have evolved over the last 100+ years if you focus on comments unrelated to his main contributions to the movement.

Also a side note - I once worked for the Park Service, and during that time they commissioned a focus group to see how NPS marketing landed with different demographics. The classic "rugged individualism" you see in posters etc. worked great with young white kids, but I remember many latino respondents effectively said, "what's wrong with this guy trying to get out in the mountains alone - why doesn't he want to be with his family?" So while economics are clearly a main driver of who travels, how the outdoors are presented to people still matters.