No preys with scars, no youngs, no recent teeth in sediments, no strandings, NO fished ones (not even, when everybody is crazy fishing anything that remains), no sonar, submarine, ships or satelite sightings...
And as sharks are cartilaginous fishes, the rest of the body is poorly known. We even might have to rename it buck-teeth shark. Is not impossible that teeth weren't sized like the rest of the body. We just don't know.
That being said, there’s something about the depth of the ocean that has always fascinated me to the point where I teeter on the edge of “abandonment of reason”. Maybe it’s the child in me that wants these creatures to still exist, yet evade study in defiance of of humanity’s technical dominance, but I could sit for extended periods of time and let my imagination run wild with it.
If somebody would say me that whereas navigating in the south pacific, near islands surrounded by deep-water areas has seen a 12m long shark-shaped animal (not whale shaped), with a yellowish body with some white spots, and big triangular teeth around 10cm long, diving under the ship... I wouldn't bat an eye. Such animal is very rare, but exists.
Is neither a whale shark, nor a Megalodon, is an extant species and has been described by science.