It's probable that damage occurred on other vehicles which set the same code, but it is too early to tell whether that has happened on yours.

Yes there are three individual pressure control solenoids contained in the solenoid assembly. The computer is only identifying a problem with one of them. It is able to do this because they have individual wires that allow the computer to control them separately. Unfortunately, if one goes bad they all have to be replaced since they are part of an assembly. Here is a picture:

Anybody that tells you the trans will need to be replaced is jumping to conclusions and may be trying to get you prepared for an unnecessarily expensive repair. The truth is that it may have sustained damage, and could require a rebuild. But it is not a given. If the vehicle has been driven a lot with the problem present, a lack of pressure could cause the transmission to slip, resulting in damage. A lot of slippage builds heat, which is bad for the fluid and causes internal damage as well. A small amount of slippage will usually not result in damage. If this has just started occurring, and is addressed promptly, the tech can do some diagnosis to determine the extent of damage. If the diagnosis leads to removal of the transmission pan, the fluid condition is an indicator of how bad the situation is. Clean red fluid is a good sign. On your vehicle, there is no transmission dipstick, fluid has to be checked by removing a plug in the transmission pan. There is a standpipe in the pan that keeps fluid from all draining when the plug is removed, but a little will come out. The reason for no dipstick is to prevent contamination from damaging the transmission. A loose dipstick or improper fluid checking technique can allow dirt to enter through the dipstick tube.

Don't assume anything, just because some vehicles had problems doesn't mean yours will also. Hopefully it will be a straightforward repair. Diagnosis is key, and a lot of diagnosis can be done without ever opening the trans. The pinpoint test for this code requires the technician to connect a scantool, and actively command the pressure solenoids while monitoring the actual pressure responses. Electrical diagnosis to check for an open circuit in the solenoid wiring is done from the electrical connector on the outside of the transmission.

If in doubt, check with some Ford dealers. I hope that you can find one you feel comfortable with. There are good and bad ones obviously. They work on vehicles like yours all the time, and they get familiar with the diagnostic procedures, whereas the independent shops do not get as much experience on any one type of vehicle.

Getting the code is just the starting point in a diagnostic process. Jumping ahead and assuming leads to misguided repair attempts and wasted money. It is worthwhile to find a conscientious tech willing to go through the proper steps before deciding what repairs are needed. If they say it needs a rebuild, they should be able to demonstrate why. The fluid will be one clue. Debris in the fluid and burnt fluid are signs of serious trouble.

In cases like this, driving the vehicle can cause the damage to worsen. Avoid driving it, and tow it in for repair if the shop is more than a few minutes away. If you absolutely have to drive it, go very easy on acceleration, and only take short trips to avoid building excessive heat.