For some reason, I do not like it when the thumb is not a representation of the image itself.
And for some reason, I never click on a 'content advisory' thumb... I just don't find them attractive. If (purely hypothetical) every member should upload a nude image tomorrow, we could have a gallery full of those unattractive content advisory thumbs... yikes ;o))

But I fully understand the thumbnail policy and I wouldn't think of questioning it...

We do not see things as they are. ǝɹɐ ǝʍ sɐ sƃuıɥʇ ǝǝs ǝʍ