Because the companies don't know what to do with them and making a quick buck off of blatant objectification is a "use" for their IPs.
Of course, it tends to destroy the IP in the long run, but most larger corporations, particularly in today's market, aren't very concerned about that. This is also a big part of what has sparked loot boxes and mobages.
I chalk up a fair amount of this stuff to simple greed, another part is that mostly males are making design decisions, and that the inmates are running the asylum. Also, that old Miyazaki quote about how most modern media isn't about people.
The biggest problem is that because the creators of many of these IPs don't see their characters as people, it's impossible for them to write human stories about them, much less design them as such. Pretty much all characters in video games, "realistic" or not, are about superheroes. And unless you resolve a superhero with a human element, they'll be heavily disconnected from reality.
Characters like Nathan Drake, or Lara Croft, are both superheroes, and it's part of why the writing is so frequently disconnected, because of a refusal to embed that into the fabric of their stories. This isn't for lack of trying, I think more writers have begun to realize this, but it's difficult to spin a story where a character has human traits when they frequently become a death dervish.