And making porn is stigmatized. That's why 99% of the porn made "just for fun" is intended to never see the light of day by anyone but the people making it.
Really, I'm not directly sure what your argument/belief/whatever is here in this post.
If there's no exchange or barter, then there's no sex work. The stigma behind sex work is that you're selling your body to someone for a price tag, and if you weren't getting paid you otherwise wouldn't be doing it with that particular person. In other words, if you aren't getting compensation out of it, you're just like anyone else with a tinder account.