Here's where I think our opinions tend to diverge, at least fromm the implication of your statement above. I believe there is solid circumstantial evidence that life is common throughout the cosmos, even if we restrict ourselves to hydrocarbon based organisms. I have pointed out these evidences in earlier posts, but just in case you missed them...

1) Life appears to have arisen on Earth almost as soon as it cooled off, even though the chemical conditions (reducing atmosphere, etc) were very different from what they are now. This suggests life is not a chance or random happening, but a reasonable result of what must be common environments on young worlds.

2) Our own planet harbors many extremophile organisms in hostile environments that exhibit conditions we expect to find throughout the universe.

3) The chemical precursors to life are found everywhere, in comets, planetary atmospheres, meteorites, even in the interstellar medium itself.

4) Laboratory experiments confirm that when chemical precursors to life are exposed to what must be common conditions on other worlds, a process of chemical combinations and reactions leading to more complex forms occurs spontaneously.

This isn't exactly a smoking gun, but I think these are very good reasons to expect that life, at least microbial life of some sort, is everywhere. Photosynthetic and multicellular organisms are something else again, these arose only after long periods of time on our own planet, and it may be possible that they are natural bottlenecks in the evolutionary development of complex life-forms.

Spectroscopic detection of oxygen atmospheres or of chlorophyll-like compounds in planetary spectra would quickly put this constraint to rest, but it's not something we can count on happening.

We have good reason to believe anaerobic microbial life is common, oxygen metabolisms rare, and multicellular life rarer still. As for intelligence, my subjective judgement is that it is extremely rare, and technical intelligence even rarer than that. As for species capable of creating technologies we might recognize at a distance, such as spaceships and radio telescopes, these are probably the rarest of all. But I would not hazard a guess at trying to quantify it.