From
Wikipedia,
On September 8, 2020, Pima County, which owns the land on which it stands, announced that it was being shut down for an "indefinite" period.
As of October, the "indefinite" period was continuing. The driveways off the highway to Old Tucson were blocked with Jersey barriers.
Also see the
Pima County web site, which both says the facility is open and closed, and what appears to be the
Old Tucson web site, which says the facility is closed.
I agree with the recommendation for the
Arizona-Sonora Desert Museum.