For a long time I have heard that since Malachi God has been silent with mankind, some calling it "prophetic silence". To what extent is this true and supported by biblical sources? This was predicted by the prophets, where did you get it? For example, before the destruction of Jerusalem by the Babylonians, God sent Jeremiah to go and tell the people and rulers of the impending fall of the country, why didn't something similar happen before the fall of Jerusalem by the Romans? We know the reasons for the fall before the Babylonians, idolatry, before the Romans there is no clear reason, God did not send prophets in the Roman period to make them convert or avoid catastrophe for what reason? Was everything already decreed and wouldn't the prophets make a difference?
I believe you might be relating the chazal in Yoma 9b:
מִשֶּׁמֵּתוּ נְבִיאִים הָאַחֲרוֹנִים חַגַּי זְכַרְיָה וּמַלְאָכִי נִסְתַּלְּקָה רוּחַ הַקֹּדֶשׁ מִיִּשְׂרָאֵל
After the last prophets Haggai, Zechariah, and Malachi died, the Divine Spirit of prophetic revelation departed from the Jewish people...