The statement of "... sedans trailing coupes and convertibles..." is much more accurate than the statement of "... Sedans don't well as collectables, and I don't see any Giulia breaking that mold....". I think that the 2017-2025 Giulia Quadrifoglio will be a collectible car from 2050 on. Yes, the price of the gas will be $20/gal then but, to drive the QV from home to some locals C&Cs will be only a $300/yr expense.I have a Giulia GTV, and for decades the sedans were worth 20 to 40 percent of the coupes. In recent years, they have increased to being worth 50 to 70 percent of the coupes which is a good thing, but proves my point about sedans trailing coupes and convertibles.
If you want to buy a future Alfa collectable, a 4C is a much safer choice.