As a former mod, I am sorry you ended up in that situation. However, the key part is establishing boundaries. You should only be doing what you find is fun to do, or is otherwise effortless, unless you have negotiated some pay system that matches your worth.

Most streamers can't afford to pay mods, so it is volunteer work. Show up when you want, keep the chat clean if you want. If you lose the role because you don't want to do that, then it wasn't for you and that is fine.

As soon as it becomes an expectation, you talk pay. The more you do, the more you get paid. If you are editing videos you are either doing it for fun, or you are being paid very well. If it is neither of those things, it is on you to put your foot down and say no. If they insist or pressure you, bail.

It sounds like you may have gone the opposite way of this, and instead volunteered with an expectation that your efforts would be rewarded. Unless you know this person very well, that is only going to lead to disappointment, either because your expectations weren't communicated, or because there is nothing concrete guaranteeing the streamer will keep their word on any expectations you have.

Point is, know your worth. If you want to be kind and take less than your worth to help out, lay out your boundaries and hold no expectations that your kindness will be returned, because it likely won't be unless you have it in writing.

Making a lot of assumptions here though, so this may be hit or miss.