How long do I need to wait before painting an interior PT plywood floor?
Recommendations vary because conditions vary. Here are the primary factors:


Initial lumber moisture content
Concrete moisture content (ongoing; dependent on ground conditions and the presence or absence of vapor barriers below)
Indoor temperature and humidity level
Effectiveness of drying mechanisms (dehumidifier, fans, etc.)


The point is that no one can give you a number. You'll have to either rely on look and feel assessment or use sensor hardware to measure moisture content. Also, follow the paint manufacturer's instructions. Some coatings are more tolerant of substrate moisture than others.