Whether we "need" a Big Three, or some other combination of auto makers is a matter of market dynamics. If they or any one of them can't survive in the current market, they should be out of business just like any other business in a free market economy, including banks and Mom & Pop stores. We don't have an over-riding "need" for any of them. Presumably, if Ford were to go out of business, the remaining auto makers would assume their market share and would be stronger for it. That's how the market works.
As for Bond, no doubt Ford contributed mightily to the funding of the film, hence all vehicles were Ford products. Money talks even in the movies. However, in light of the current issues with Ford and others claiming to be loosing their shorts, why would Ford be in a position to contribute to a mere movie to such an extent that they would lock in the brand names of all vehicles used? Or, having deemed it possible to make such a contribution to a mere movie, why would Ford now cry about their profits and need government support?