Is there one single urban public observation tower still open in the State of Texas that isn't part of a publicly funded entity? No, I wouldn't include the COTA tower - that's ridiculous. There was one in Houston I believe, in one of the 80"s skyscrapers Downtown, but I bet that closed.
Maybe Reunion Tower in Dallas, if that's still open? I would guess that entire complex was publicly, or partially publicly, funded, however.
An urban observation tower is by its nature a communal experience and, as much as most Forum members love their developers, communal is just a short slippery slope from communism.