Guy Fawkes walks into a Samurai bar...
The Katana is absolutely a meta-shaper straight out of the box. When you are learning the game, this is the ICE that teaches runners to facecheck Jinteki with caution until their killer is found. 3 net damage can set a runner back if not outright kill them. Once rezzed, the sword will keep runners who can't break it out.
Here's the little exercise that everyone does with the core set. It teaches faction strengths and weaknesses, deckbuilding strategies, AND basic math skills.
How Much Does It Cost to Get Through Neural Katana?
Ding ding ding! The cheapest-to-install killer of the bunch breaks through Katana for 3-5 times less than the competition. And Mimic only costs 1 influence, so every runner can use it! As a bonus, we also see why no one uses Pipeline.
So for your 4 to rez, you're probably getting a 1 tax per run. That's atrociously bad. So the corp learns to only rez this if it'll fire, and to just install over it if they have a Mimic on the table.
EDIT: It's notable that Katana has the highest damage of any hard damage subroutine (barring situational Cortex Lock), making it the best candidate for Batty kill). Thx @WayneMcPain for pointing this out!
Katana will probably never be used unless a Core Set 2.0 errata occurs where its rez cost is halved, or Mimic's install and/or influence costs would increase.