Older Subies were FWD then 4WD. The 4WD was "Four High" only and could be engaged with a switch. Then they went AWD. Full-Time All-Wheel Drive. Anything I've ever seen or heard about those is that they ARE flat towable ONLY WITH Manual Transmission.
Part of the confusion may be that we are talking about "recreational towing" of a working vehicle behind an RV over a long distance and high speed. Not "disabled/damaged vehicle towing" with a tow truck or wrecker for several miles. I would NOT want to tow an AWD with any kind of driveline problem on anything but a flatbed wrecker.