Do I need an adapter to charge my iPhone in Italy?

You can use the same power adapter (charger) that you are using now......because it will automatically work from 100-240 Volts and 50/60 Hz.

But....you will need a wall plug adapter to connect the U.S. plug to the wall jack in Italy. Amazon has them:

https://www.amazon.com/Unidapt-European-Adapter-Converter-adaptor/dp/B077WJYNQ5/ref=asc_df_B077WJYNQ5?mcid=499a00296aa53d16bd670a6b677b2089&tag=hyprod-20&linkCode=df0&hvadid=693392717738&hvpos=&hvnetw=g&hvrand=1310221183825127194&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9027201&hvtargid=pla-399994892565&th=1

Or, you can pay 3 times as much at the airport travel shops and tourist shops.

Apple sells a world traveler adapter. You'll need this or you can also look on Amazon if you want to pay less --> Apple World Travel Adapter Kit - Apple

The Apple kit is a nice package, but you really only get one adapter that will work in a given country.

Most folks will need at least 4-5 adapters to cover the laptop, iPhones, razor, hairdryer etc.

True, if they will be taking multiple devices. The Author only mentioned iPhone XS and iPhone 8. But yes, if they will also take a laptop, iPad or pretty much anything else they need to charge, they'll need multiple power adapters OR charge devices at different times while traveling.