I didn't assume that. This post isn't about Babel, it's about the "JavaScript community", which you are being paid to work with.
> The vast majority of open source maintainers are not paid in anyway whatsoever.
I know. I'm one of them. I spend ~20 hours a week on open source on top of my full-time job. I know how stressful it can be, but I'll never complain about it because it's my choice to be involved. I'll definitely not be complaining about it if that 20 hours was something I was being materially compensated for.
> Conferences pay me to fly places and stay in hotels because they make a profit off of me.
Yes, this is how business works. Work is exchanged for tickets and advertising. Part of the work is being a presentable and knowledgeable speaker who can effectively engage and relate to the problems expressed by the audience.
> I don't think a single person on my team would expect me to tolerate people yelling at me.
If there are people harassing you that is indeed a problem -- get the police involved. That seems a completely separate issue from what's discussed in this post though, which is a community that sometimes discusses technical arguments in a way you consider abrasive.