My theories are:

(1) Berlusconi's desire was to be seen not as a tough person. He played with your selfish desire to be wealthier rather than with your anger. Salvini doesn't care.

(2) Berlusconi lived in a pre-Internet era, so most information was delivered by old media, which were filtered to avoid alienating audiences and to respect decorum. Social media do not have such a limit.

(3) Berlusconi was toast after the 2008 financial crisis. Salvini's #Italy is in a worse position.