1. Free = problematic with the lack of money
2. Freemium = looks good if the balance is right
3. Ads = Mostly works but the model is flawed and skewed
4. Subscription = Love/Hate currently trendy but too relied on
5. Pay-what-you-can = Fans provide the service for everyone
6. Premium only = Only what it's worth, when it's worth
7. Enterprise = S'ok because my company/org pays for it
8. Tokenised = S'ok because the next person pays for mine...
9. Charitable / foundation = Someone more wealthy pays
10. None of the above = For now somehow it works
There are probably 10 more models already, 10 more out there and 10 more coming soon. Get thinking, stop complaining.