Is there really life in Europa's oceans?

The thing is, "life" could mean very different things. If you mean microbes or basic life forms, the probability is pretty high given what we know about the environment beneath Europa's ice - liquid water, possible thermal sources, minerals. If you're hoping to find intelligent squid, then we're way more in the realm of speculation. The scientific community is genuinely convinced the conditions are there, but until someone sends a probe down there and brings back samples, we're stuck in the field of educated guessing.

What strikes me is the difference between "theoretically possible" and "we have proof." We know Europa has an ocean, that's true. We know there are probably interesting chemical reactions happening. But missions to actually go look are expensive, complicated, and we haven't done them yet. In 2026 we're still basically waiting. Satellites tell us interesting stuff from the outside, but it's like trying to figure out if someone's home by looking at the windows from far away.

Personally I find it fascinating that in our solar system the place where we might most easily find life could be not the usual Mars everyone imagines, but some distant moon of Jupiter. But until we go there and look, it's all hot air. Scientists have good reasons to be optimistic, but optimism isn't the same as certainty.