Can you point to me where it was made illegal to require a mask on private property in Texas (other than perhaps for certain disabled persons per ADA)?

My understanding is masks mandates were only banned in places like public schools, where the owner is the public thus the individual public student has the decision to wear a mask or not. I would certainly disagree with this sort of control on private school, although I might add it could be a public health risk to mandate masks in school as it could harm the linguistic health of some young children developing language skills.