It’s explained here - https://taxing.it/tax-break-to-attract-human-capital-to-italy/ - 90% of income is tax free if you move to Italy from abroad (70% in northern Italy). Word of warning, they’re currently contemplating reducing the %. Right now max. income tax you can pay is 4.5% (45% on the 10% that is taxable). Western part of Napoli is great plus you have Amalfi Coast + Capri/Ischia etc right there. Weather and food also amazing.

I’m originally German, spent >10y in London and recently moved to Napoli, Italy (they have a great tax break for people who want to move here).
While it’s not true for Italy more broadly, Naples seems to be on the upswing. It’s at least to some degree due to increasing number of tourists. However, it’s worth noting the starting point is naturally lower than in northern Italy (where I think things are getting worse)