No, this is wrong. As the others have said, "Brückentag" is a general term for non-holidays, and it doesn't even apply here as Friday is the holiday and not Thursday.
Good Friday is also still very significant in its religious purpose here, so calling it "bridge day", even if it applied, would be disrespectful.
(Which doesn't keep the racing/modding community from having their own "Car Freitag" on that day...)
Any day between holidays and weekend is a "Brückentag", a bridge day. Friday would be a bridge day, if thursday were a public holiday. So would monday, if tuesday were one. It's not a term a for specific day, but for a type of day.
Well, ascension day and the corpus christ feast are always on a thursday and as such the friday after them are Brückentage, but in my lifetime at least the good friday not once was on a thursday...
Good Friday is also still very significant in its religious purpose here, so calling it "bridge day", even if it applied, would be disrespectful.
(Which doesn't keep the racing/modding community from having their own "Car Freitag" on that day...)