Aikido and Judo are both Gendai Budo-modern Japanese martial arts. Between the two, you'll get a pretty comprehensive overview of many Koryu (Japanese old schools) Jujutsu/Aikijujutsu technical syllabus.
This is simply not correct
I have never met anyone actually ...in...koryu (not just iai) who would ever make that statement.
Aikido™ has nothing in it to give a student a comprehensive overview
of Koryu: the movement, maai, weapons handling, intent, angles, and approach are much different.
Nor is it going to give you a comprehensive overview
And Aikido™ doesn't function like koryu jujutsu.