Not unique - there's a cheese-shop up the road that sells a mature Gruyère that is quite different from their standard-price Gruyère, which in turn is quite unlike supermarket Gruyère. And that's all on the Swiss side of the border - Comté is the same stuff, but made 100 metres away.
There are many regional variations and qualities of Comté, too.
When De Gaulle asked "How can you govern a country with 200 different cheeses", he was underestimating badly.
One of the legends points out the similarity with Gruyére, but it still calls the French cheese Comté:
"Le fromage de Comté, analogue du Gruyére suisse, se differencie de l' Emmental..."
That's very common. In Greece for instance there's a PDO cheese called "kasseri" but all of northern Greece calls all hard or yellow cheeses "kasseri". Conversely, they call all white cheeses "tyri" ("cheese"), which usually (but not always) means feta, which is in turn a PDO name for a specific kind of white cheese made in certain areas of Greece only.
I guess it's the same thing with French cheeses and Italian cheeses, and every other place's cheeses. Heh.
With the help of my local cheese shop (mentioned upthread) I came across what they call "proper" emmental, which is a very mature emmental, a bit like a mature gouda. Only a bit rubbery. And silly expensive, but very nice.