But Aikido mostly seems to attack with the knife in the traditional Japanese way ???
Because if the methodologies evolved to fit contemporary knife, it would compromise the "skills" of some sensei and shihan mostly those who did not possess or attain those skills in the first place.
There are quite a few here, look around.
The flags are there.....no skilled or experienced martial artists accepted to their training, no proper taisabaki/kuzushi, no unrehearsed attacks, target audience is the gullible non-confrontational newbie, or the "fantasy fighter"....open your eyes they are there.