The problem with the meaning of “intifada” is that in the US at least, and some other English-speaking countries, it has strong connotations of violence and terrorism dating at least to the 2nd Intifada. The “correct meaning” then becomes somewhat beside the point. Further, if someone in the US uses that term, when speaking in English, it raises a question of which sense they mean it in.
There’s no doubt that this is then used as a weapon against people like Mamdani for having used phrases such as “globalize the intifada.” But that’s going to be an uphill battle to “correct”, because you’re dealing with people who are already biased, are often unaware of their bias, and are interpreting things in a way that fits that bias.