I use mine as a daily driver and don’t have nor have I needed a back up. I have only had scheduled services performed and am provided with a loaner.
Count yourself lucky then I guess. The Alfa Romeo dealer network seems to be marginally better in Europe than elsewhere but they're not great there either. Just look at how poorly they fare virtually every reliability and customer satisfaction survey or ranking.
Here in the USA there are many reports about simple problems that should take mere hours or days to resolve that end up taking weeks or months due to unqualified/ inexperienced technicians and service advisors, poor service information and tools, poor parts supply, etc. There is no guarantee of loaner cars. 16000km is nothing and if you're saving gas in a QV you're doing it wrong. Gas is not practically free here. Yes, it's cheaper than the EU but it's hard to make an apples to apples comparison between standards of living. Price/gallon at the gas pump is just one variable of many that affect "affordability" and living standards.
One unlucky stone chip could turn into a cracked windshield and a car that's unsafe to drive until repaired. Most dealers don't do window glass replacement - they subcontract it out - but even places like Safelite were running into supply issues. There have been several reports of windshields being back ordered indefinitely with no ETA. Eventually customers got their cars fixed, but not without great delay. Again, no loaners for many customers.