There's evidence, it's just modest. I recall the outcry around here when it was pointed out that the number of known exoplanets was going to increase by multiples due to the improvement of observatory technology. Speculation is, there isn't any other intelligent life because you don't want there to be any.
You might even say, there’s evidence, it just isn’t publicly available...yet.
Again, the sheer number of planets in the universe is not evidence in itself. Most of them will be around stars that are unstable flare stars, multiple star systems, don’t have enough heavy elements, or are too short-lived. Then there are the planets themselves. Most will not be in the habitable zone, are gas giants, have no water, etc. It is said that without a moon the size of ours, Earth’s tilt would be too unstable for life. We don’t know how rare that is in the universe. There is also a magnetic field that is needed, perhaps a fractured crust, etc. etc. There could be dozens, hundreds, or thousands of other factors which would make life impossible. Earth itself has had several extinction events which very nearly wiped out all life. I don’t think it’s pessimistic to consider this, I think it’s realistic.