Ford Fairmont headlight issue common?

It's not an issue that has come to our attention here at Carsguide, which would suggest it's not as common as your mechanic believes. As for a recall, they're usually associated with safety issues and the failure of a headlight switch would not normally fall in that category. Car companies do, however, have low-key service rectification programs in which they fix cars when they have a widespread failure problem with a particular part. That would be the way they would address a failure such as the one you experienced, but only if it was widespread and only if the carmaker had a community spirit.