Yes, nowadays there are many so called "Specialists", it almost seems as if anybody that works on a particular brand of car for a couple years labels himself a "Specialist". No former factory training, no access to Factory information, they just work on a few jobs and see the opportunity to "cash in" on a particular brand of car and then they just use the label on all their advertising.
On the other hand, you have shop owners like Renato Natale, owner of Renato's Auto Service, a true Certified Technician for the last 25 years. He specializes in service of Mercedes Benz automobiles.