Comments
Making money from Twitch or blogging is very difficult. I think you'll enjoy the process of blogging/streaming a lot more if you aren't doing it with revenue in mind, at least until you reach a reasonable following.
For perspective: Twitch streamers make ~$3.50/month/subscriber. If your job pays, say, $50/hour, you'd need 100 Twitch subscribers (which I'd guess would take months to accomplish even if your stream is polished and highly watchable from the beginning) to pull in revenue equivalent to working seven more hours each month.
(Of course, you may not be able to "add hours" in that fashion, but I still find the comparison helpful -- and you may be able to do some freelance consulting or something like that.)
This seems like a classic case of it being okay to have more than one goal. Your hobbies can be hobbies without having to be impactful; your work, if it is your primary source of impact, seems like a better place to focus if you want to boost that impact.
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All that aside, if you do build a strong following on a blog or stream, that can be a good opportunity to advertise effective giving, and it probably won't hurt donations if you mention that they go toward really good charities.* I've considered doing this if I ever open my own Twitch stream up for donations.
*...although, come to think of it, many people probably donate to streamers/bloggers in order to support their work/the cool person behind it. So perhaps the charity angle would hurt more than it helped?
What do you want out of your time?
Immediate lives saved? Impact on the distant future? Building new skills? Widening your professional network? Having a good time?
Once you know what you want, and which of the above you consider to be "effective" uses of your time, you'll have a better answer to your question.
More in the same vein in this article: https://forum.effectivealtruism.org/posts/ScLHyCY6JCr5FtuiY/effective-volunteering
Maybe "effective" is the wrong word to describe my feelings about this.
To piggy off of aarongertler's comment - it seems like I have more than one goal of what I want out of my time. Through my day job, I want to save lives, have impact on the distant feature, build new skills and widen my professional network. I'm very fortunate that I get all those things and have a good time as well.
Whereas blogging and Twitch streaming, I want to have a good time doing it, but also make an impact so that I feel much more satisfied/fulfilled/motivated in doing it. Otherwise, my fear is that it would become a waste of time.