You shouldn't reject crash cases based on a priori assumption. Our own experience shows advancing technology does not mean invulnerability. Look at all the times when our spacecraft, navigating interplanetary hazards, crashed on other planets or the moon or just missed. Roswell, Kecksburg and a few others seem credible enough.
Many smaller scout craft may be lacking both offensive and protective assets so they've lost a few.
I wish I had a buck for every report of humanoids associated with UFOs.
Your idea of a humanoid has the following notified condition.
1. the human psyche used by all humans as a status of self awareness, personal ownership due to the condition of personally owning a particular amount of irradiation when the natural cells were forming. All human selves are different due to the amount of radiation interacting with cell forming....we are only living due to the sexual act, why our psyche is differently expressed.
2. human sciences as an awareness was first gained by the human males as a mind/psyche concept, and thinking today still involves the status and personal condition of self awareness.
3. the atmosphere is known to hold transmissions....SION the condition of conscious awareness and spiritual consideration....known by all occultists.
4. the atmosphere can record both image and sound in the natural and unnatural amount of photonic interaction and increased nuclear fall out conditions.
5. the human and natural life recorded (as a reflective atmospheric image body) in this way and unnatural communications the conditions of nuclear science.
6. photonic recordings in the atmosphere as a huge amount communicate and communicate as a natural/unnatural effect. The unnatural communications/images have therefore multiplied to a huge mass condition.
7. the human brain and natural chemical cell condition irradiated and given an unnatural atmospheric communication effect/interaction.....receives a multitude of unnatural imagery transmitted back to the mind.
8. this causes the unnatural condition of feeling the irradiation conversions personally due to UFO fallout conditions/nuclear conversions whilst also gaining the interactive transmitted imagery of natural atmospheric radiated light sound un evolving-gases burning as fallout.
The status of de-evolution states the image recorded in natural cooled radiated light/life sound would change in the changing nuclear light sound transmitted interactions. It might record a human life as an image, but eventually that life image would begin to convert in the nuclear sound change interaction gaining a lesser and much uglier looking transmitted message/image. The human witnessing the destruction of natural life is warned by this condition as they are seeing their own future images in a lesser and hotter radiated light mass sound due to atmospheric losses.
As the atmosphere is the psychic warning system, the loss of atmospheric mass and its natural replacement condition is advising the human nature of what it will look like as a future image if it does not stop abusing the only holiness it owns.....the only life condition of the natural life, natural atmospheric cooling and replacement.
Historical evidence attests that the human life once existed in a much uglier and deformed nature that re-evolved to atmospheric cooling and amassing...from a non applied occultist condition...no sciences.