: I've only seen a few episodes of the series so I might be wrong on this, but
: IIRC the best weapons humanity has are cannons. Combined with Titans
: possessing some regenerative abilities, it means that they can't put out
: enough firepower to stop them, especially against multiple Titans at once.
: Unless they hit the weak point in the neck, the best they can hope for is
: slowing the Titans down.

They have used the guns and titans' eyes in a clever manner from time to time, but that, and the bloody titans fully regenerate after any attack that is not the kill-point of their neck, so cannons can only slow down titans. So many people die in the story unless you become part of the main cast, it's like Gears of War: the anime.

It's a series with a medieval tech level with the steampunk tech that is the 3D Maneuver Gear that makes them go like spiderman redshirts. Add to that with the fact they seem to be ruled by a dogmatic government that keeps the truth of a lot of matters and technology (including maps of the bloody world and what oceans used to be!), and how little life has a value even among humans themselves, and it turns clear how fucked humans are in that world.