Awesome post, though I have a few thoughts:
(The above was edited for clarity.)

While I can see why the average movie goer would think Annihilation was too intelligent, I can't buy that Mother! was an intellectual movie. I loved both but the latter was very on the nose and obvious. I would say that Mother! is definitely more of an art house style film.

I mostly think that Annihilation was a victim of marketing more than being too smart of a film. Not only the marketing, but it was dumped into the January and February release slots where studios push movies that they don't believe will have success.

I did find it funny however that unlike Ghostbusters (2016) and Wonder Woman had the marketing and media push of being movies with women leads, but Annihilation wasn't despite it being full of women in STEM fields and Doctorates doing some smart things and making Discoveries. Meanwhile Ghostbusters characters were cliche, the jokes were dumb and immature, and it laughed at the expense of its source material.

Overall I think you made some great points and it is well worth considering. We find ourselves in a time when media distribution has lost its way and is trying to find its future. As an avid film fanatic I hope we can get back to seeing smart and intelligent films have mainstream success.

Thank you again for this great piece of content! I hope to see you around.