Counterpoint: universities exist to teach young people to be competent, well rounded members of society, including exposure to quality academics, music, art and sport. If you just want job training, go to trade school; if you just want academics, go to the library.
If you’re trying to avoid a whole zigbee or zwave network, Govee makes some inexpensive battery-powered bluetooth thermometer/hygrometers, and have a HA integration, but bluetooth can be tricky to get running on Pis. I feel like most of the actual wifi devices are phone-home type setups. My govee thermometers have pretty good range - one of them even reads from inside the refrigerator.