You can. But you must pay this 100k flat /annualy. And is only for foreign source income. I dont know how it's interpreted if you trade cryptos in Italy without tax.... Would it be local or not. Such regimes don't stay forever. Government can change it any time.
I am a big sceptic of such regimes as Portugal HNWI, Italy 100k flat etc..
You also have to deal with Italian authorities about your source of wealth, source of funds.
Usually such regimes has many many strings attached and is very "complex"
For me more clear is 0%
income tax. Like UAE , Monaco, Bahamas etc.
Also once you become resident of Italy if such regime change, you would have big problems exiting Italy