Subscriptions may work, it obviously won't be for everyone, but maybe it doesn't have to be either. Maybe it can be a luxury product for people with pockets as deep as their dissatisfaction with what's on offer for free.
Third option is what, donations? As someone running something like a donation-funded search engine and makes about $100/month doing so, it doesn't seem to work out very well. Admittedly it's a limited offering that focuses on a fairly specific niche of websites, and I'm not really going full Jimmy Wales in pleading for money on every other page.
People in general don't seem to want to pay for free services.
Like what's left, crypto microtransactions? I don't really feel that would work either if nothing else because most people just don't own cryptocurrencies to pay with.