Recalls 1 and 3 describe the same defroster defect. I'll treat them as one issue.
The 1990 Subaru Legacy has 3 recalls, the most serious being a defroster that can stop working entirely, leaving the windshield unable to clear in cold or humid conditions and reducing the driver's forward visibility.
The defroster shutter door's lever pin can slip out of position, letting the shutter close and cutting off airflow to the windshield. This affects sedans and station wagons. On the structural side, also specific to sedans and station wagons, the front door latch screws can loosen and fall out, leaving occupants unable to open the affected door from the inside. In an emergency where a quick exit is needed, that failure could trap a passenger in the vehicle.