further in my humble poor opinion; If the only way to secure funding/guarantee your product/job/life is by having completely irrelevant, predatory ads hosted in your space, maybe you should go int oa different field, or not expect to make money off of a niche hobby application.
Hosting a website, app, service, (if not a paid service), should be "cost of doing business". Or "cost of maintaining a hobby which I'm broadcasting." It is a great disservice to our children that the "default" in life is "you will pay for this ,and you will watch brain rot ads"
This said, I see three more ways for free (like gratis) services (at least free for users):
1. Government-funded services. If some online services are deemed to be very important for public wellbeing, the government might decide to pay for a service or to run it themselves. One example is public databases like a list of medication covered by health insurance.
2. Non-profits. They can live off voluntary donations from users, governments, and companies.
3. Hobbyist-supported services. People work pro bono to support a service and some hobbyists even pay for third-party services (like hosting).
These are not sharply discerned categories. A service might nominally be run by a non-profit, but the non-profit is staffed by hobbyists and the government might pay for hosting and other costs. Such a service would be a government-funded hobbyist service run by a non-profit.