No, I think the majority of cis people do not understand gender, including their own, because they have no need to really think about it.

As you are demonstrating by saying it is "oppressive"

Some aspects of gender are indeed oppressive. Forced specific gender presentation. Men being told they can't cry. But these are not gender itself and are typically forced by people who believe your genitals determine your destiny. Those things are oppressive. And they are applied to cis and trans alike and often more to trans people, especially trans women who are expected to...I have a trans woman friend who has to wear a full face of makeup to every medical appointment so she doesn't get asked if she's ready to detransition now. Not an exaggeration or a joke.

But what about the concept of gender oppresses you? Why do you feel this way?