Why hasn’t God intervened on the tyrants throughout history to prevent far worse atrocities than in the Old Testament days in which He did intervene?
A tyrant is a king or ruler who uses his power oppressively or unjustly. Any despotic person.
Tyranny is the arbitrary or unrestrained exercise of power, despotic abuse of power; oppression
The tyrants in the earth are becoming plainly visible and God has every intention of intervening!
Thus saith the LORD, “To Me belongs vengeance, and recompense; their foot shall slide in due time: for the day of their calamity is at hand, and the things that shall come upon them make haste… And He shall say, ‘Where are their gods, their rock in whom they trusted?'”Deuteronomy 32:35-37