I agree. Get a new windscreen.

I had those editions of the Focus and it annoyed me. You should be able to squirt enough wash onto the screen and then engage the wipers. What has happened is that dirt, grit and small stones have accumulated along the wiper blades. They are against the screen and make a perefect ledge for this debris to rest on. As you've squirted the screenwash the wipers start automatically to wipe across the screen. Not enough water to aid the blades properly so dry patches are wiped across with this dirt and grit which scratches the screen. Over time, you have no option but to replace.

Ideally I would like Ford to have a washer that squirts before the wipers are activated by the driver and have the wiper arms "park" along the A pillars, so vertical. That way dirt and grit should not collect as before along the wiper blades. Which should reduce the scratching you have encountered.

Ford still don't learn. I have a 2013 Focus. If I lift the wiper arms to clean the car, then replace in position, when I start the car, the wipers do a realignment wipe across the dry screen. I usually have to switch on igniton while they are off the screen. Let them realign in thin air. Switch off ignition and replace onto the screen. Otherwise if you forget and start the car later in the day or days later, you get that realignment wipe, which if dirt is on the parked blades, they drag all that rubbish across a dry screen. Not good.

When you do get a new screen fitted, make sure you wipe the blades on a regular basis especially after rain or when the car has been parked for long periods. It wont stop this nuisance but it will help.