I disagree with Buick. While
I disagree with Buick. While they have a long row to hoe, they are pulling themselves out of the "old people" association and leaving that to Lexus. They sell a moderate volume of cars and have been for decades.
With Fisker and Tesla, they're too new and I consider them niche makers, not mainstream. Right now, they're tiny little companies making a handful of cars.
Lincoln does very well in sales and is actually one of Ford's top brands by volume. Ford was right to dump Mercury, but Lincoln is a good seller and it doesn't compete with their other lineups (something GM hasn't yet learned to consider).