There's merit to your question. Ultimately, as someone who largely hadn't taken theory seriously until the last couple of years, I think theory is not only useful, but necessary. There are good comrades who do good work without theory, I don't want to discredit that. However, theory has had a profound impact on my understanding of history, tactics, and life itself. Theory is important because our predecessors have given their lives discovering and handing down the lessons they've learned.

From Marx, who dedicated his entire life to discovering the mechanisms of Capitalism to give the Proletariat the tools to surpass it, to Lenin, who analyzed Capitalism's monstrous evolution to Imperialism, to Gramsci who spent the later years of his life rotting in prison and reflecting on Marxian teachings, to Politzer who stood against the Nazis and taught Parisan workers Dialectical and Historical Materialism before being captured and executed for his Jewish heritage and Communist alliance, to modern theoreticians such as Losurdo, Parenti, and the many Communists who dedicated their lives to the working class. Revolutionaries like Mao, Fidel, Guevara, Ho Chi Minh, Lenin, and more all have unique lessons to tell from their experiences in their existence. People like Mao, Deng, Xi, Zhou Enlai, Liu Shaoqi, and more have helped build and design the largest economy in the world. What can we learn from them? What should we copy, what should change?

We owe it to them to learn from the lessons they dedicated their lives to teaching us. We have a duty to humanity to move beyond the wretched system of Capitalism before the planet is destroyed by Climate Change for the pursuit of profit. We owe it to our predecessors to continue the work they started. We owe it to our successors to use the best tools we can to make their struggles easier. We owe it to ourselves, so that we have a future.

Theory is a tool. If you don't take every advantage you can against the most heartless, greedy, brutal Empire in history, do you really care at all? If you refuse to truly learn your enemy, in all its complicated facets of expropriation, or learn the successful tactics and strategies for overcoming them, or learn from the missteps of our predecessors or the correct actions they've taken, we will not have a decisive victory.