I agree. If some mathematicians purposeful obfuscated or made more complicated than necessary certain topics, it would create an arbitrage opportunity for others to clarify and simplify the topic.
There are definitely tangible rewards for those who can clarify and simplify a topic, because it can lead to discoveries and insights.
This gradual clarification of a topic hinges on the actual importance of the topic. If a topic is not important, I can see people getting away with obfuscating or complicating results.
Respectable, pro mathematicians don't obfuscate. But there are definitely math professors in non-top universities who get kicks out of torturing students and think "this is supposed to be hard" etc. I'm definitely a math enthusiast but I have personally met people like that. Typically the exams are under strong time pressure and are more about rote learning of fixed types of exercises and remembering definitions.
On the other hand, I had math profs who radiated curiosity and fun and the exams were just a few questions, but you had to think to solve them and you weren't under much time pressure.
So while mathematicians aren't purposefully obscure, the math people (teachers) the average person interacts with are sometimes purposefully obscure.
There are definitely tangible rewards for those who can clarify and simplify a topic, because it can lead to discoveries and insights.
This gradual clarification of a topic hinges on the actual importance of the topic. If a topic is not important, I can see people getting away with obfuscating or complicating results.