Going out of your way to voluntarily choose to post your work on the internet, and on social media specifically, in order to market yourself and connect with new readers, is unpaid labor?
No it's not. It's being sour that you live in an interconnected world where others might find a way to benefit as a side effect of your own efforts.
Of course these are just opinions. It just doesn't seem like a perspective that's serving them well, except to make them feel bad about the art that they've been putting out… in the same way… for years and years… unchanged… with no tangible new issues for them or their readers… except the optional sadness that comes from this optional choice to be upset that other people are making money.
If you can't understand why somebody would "choose" to be upset that they're struggling to subsist while a company worth billions is using their labor without compensation to generate revenue, you're not worth discussing this with.
Their struggle to subsist has literally nothing to do with this other party's profits.
By their own admission, their struggle to subsist was a choice. It was a choice they made before these social media companies even existed. And they deliberately chose to continue with the same poorly-performing model that didn't make money, because they preferred doing it that way.
And now they are sad that others have not made that same choice, and are making money.
Why do you keep leaving out the part where the "others" are making their money using the unpaid labor of this artist and many, many others, without compensating them for it? Are you seriously suggesting that this artist should stop expressing their upset because they have the option to build a plagiarism machine instead?