Two differences: react (and other) conferences are intended to serve a dual mandate of advocacy for a specific method and general education of attendees who may not be knowledgeable about the topic at hand. Even if I write spring boot/asp.net core all day, learning about react isn't exactly a big deal.

In the case of protests, you seek to advocate for a specific course of action. It would be more akin to me sending a JEP or whatever the equivalent is for react. I would rightfully be called foolish for doing so, as I know very little about react and should choose to educate myself before attempting to advocate for a specific course of action.

I don't see the incongruence here.