Don't just go by the car's initial price - that's the mistake a lot of people make. What really matters is how much you're going to drive annually and how long you plan to keep the car. If you do less than 15,000 km a year or you're going to sell it in three or four years, gasoline is probably the better choice because diesels need long distances to make up for their higher initial and maintenance costs. Fuel injectors, particulate filters, and diesel engine repairs are more expensive if something goes wrong.
That said, if you drive quite a bit (more than 20,000 km annually) and plan to keep the car for at least five years, diesel is still more economical on fuel, though I'll admit the gap has narrowed compared to a decade ago. The issue of gas stations closing is real in some places, but most major cities still have good diesel coverage. What has changed is that some municipalities have started to discourage diesels with restrictions or higher taxes, so it's worth checking if your area has anything like that.
My advice: look at how many km you typically do in a month and calculate the fuel cost for both options over a five-year period. Add the maintenance (diesel is pricier there) and compare. The 308 is reliable in both versions, so the decision really comes down to your driving pattern, not which one is "better" in general.