It’s also reasonable for any science or discipline to advance and change over time, but generally it does so through discovering new avenues of study or refining existing understanding. What we know about, say, physics has changed a lot over the years, but it’s usually in the context of learning more about the world and adding that learning to the existing knowledge, and occasionally tossing out some flawed aspect of understanding, but at the end of the day, there’s no real chance that someone is going to be like “Wow, turns out those laws of thermodynamics were way off.”

Same with Marxist theory. Trying to apply something like labor theory of value in a specific and quantitative way can end up in weird places and not really work out (depending on what you’re trying to prove), but the fundamental concept that value is created when labor does things, and that extraction of surplus value is roughly where “profit” comes from in a capitalist framework, isn’t going to just suddenly stop being valid, and if you have so little faith in those fundamentals that you can’t let people arrive at those conclusions on their own, then not only are you alienating people who would otherwise be sympathetic, you’re dismissing the possibility that they might have something meaningful to contribute, either to the discipline itself or in the application and/or framing.

Dogma is a problem because it represents stagnation, not because dogma can’t be correct. Letting people question dogma allows for greater understanding and broadens support as people come to realize that it makes sense. Not letting people question dogma leads to alienation and isolation.