Yes, it could be a loss for the sake of variety, and even if Chrysler's current range is garbage right now, there's nothing to say that there own spin on Fiat sourced products wouldn't be desirable in their own right.
Still, other stories on this have stated that while Chrysler and Dodge recedes in markets like Europe and Asia, Lancia will be "twinned" with Chrysler and their products shared.
That's the real underlying story here. In a very real sense, this could mean that Chrysler products will be badged as Lancias moving forward. I think this is probably the better move for markets like Europe as Lancia would probably be a much more successful brand, if only because it is European. A "new Thesis" (could they call it Thema or Aurelia instead of Thesis?) based on the Chrysler 300 mechanical might do well in some European and world markets.
Still, Lancia does not exist in places like South America and would hope that Chrysler would retain the brand in that market rather than have them confined solely to North America.
I'd like to see how this plays out...