A radar sighting isn't physical evidence. It's a blip.
It results from a physical object, unless it's a temperature inversion or some such. But radar sightings have been supplemented by visual sightings of strange craft.
As to the rest, there are traces, damage and injuries, but not a lot. And how much of it can be proven to represent something of unknown technology?
There have been quite a few landing trace cases, or other evidence such as magnesium of a purity unattainable on Earth at the time it was obtained.
Some photos such as McMinnville have never been debunked for decades.Most photos can be faked; it's a lot easier nowadays.
Sure, we laymen are.I'm not saying some UFOs don't represent unknown objects or phenomena. But we're still far away from understanding fully what's going on.