I am not discounting the points you've made. I understand that there are definitely cases where 10% might be too high. Hell, it might even be applicable here.
Respectively, I disagree with your quoted comment. Are you sure its zero? Uber Rush delivery drivers make 75-80%. Where do you think the rest of the delivery fee goes? This was just from my first Google. I am sure you can find more examples of this being not the case.
Going back to the topic at hand. For a dev like me, I think 10% is high but agree with the points made. There are 100s of posts online of people writing shit for free. I am sure you can even find a dozen of subreddits alone for writing. From their POV this can be seen as a secondary source of income.
Most people who are GOOD writers - at a point where anyone would buy their 'product - have been writing for many years. They could even be doing this as a profession (think book writers). For them, do also see 10% being a high fee?
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> I just think it’s foolish once revenue hits a certain point.
including your edit are home run!