Trotskyism is essentially backwards, and rejects the revolutionary role of the peasantry. In essense, in modern days, it plays the role of "left" anticommunist, attack dog of empire against the legitimacy of AES on the left. That's ignoring Trotsky's treason, and allowing personal grudges to overtake his politics later in life. As an example of Trotskyism in action, the Chinese Trotskyists wished to fight Imperial Japan and the Kuomintang at the same time, knowing it would be suicide.
In short, Trotskyism is theoretically backwards and less developed than Marxism-Leninism, and Trotskyites in practice has historically served empire and opposed socialism in real life. Trotskyism, in the global context, is a fringe subcategory of Marxism largely found in western countries and pockets of Latin America. It's the epitome of the failures of "Western Marxism."
Most egregiously, Permanent Revolution is already a failure, the soviets were able to ally the proletariat with the peasantry and establish socialism, and continue to do so in AES countries today. Had the soviets committed to attacking the peasantry and merely hoping the western European working class would save them from the backlash, the Soviet Union would have fallen in the 20s-30s.