Oh, really? Why? I don't know about ASU dojos like your old one (I peaked at the web site), but in the dojos I've been to, Koshi nage isn't the first technique new people learn. The Seidokan dojo I was in in the 1980s never got to things like it or aiki-otoshi, so I spent almost twenty years thinking Aikido didn't have those things! It's not listed at all in Best Aikido: The Fundamentals by O Sensei's son and grandson (although the Doshu' sequel does cover them). It appears to be something introduced at an "intermediate" level if you want to call it that. Judo, obviously, gets to hip throws sooner, and if they are harder than the Aikido version, then it makes sense that a senior Judo student would be better acquainted with those kind of falls than an Aikido student at the same level. This is because the two arts have different emphasis and different curricula. Neither is right or wrong, just different.
Oh, and BTW, I haven't seen hip throws in the grappling systems I've been introduced to as part of Kali. That doesn't mean they're not there, but I haven't seen them yet. And I've been doing Kali continuously for seven years.
The basic hip throw is a fundemental basic technique in many martial arts, inluding Ju Jitsu, Judo, Brazilian jiu Jitsu, Karate, Aikido, TKD, etc. By telling me that koshinage is an advanced technique in Aikido does not give me any more confidence in Aikido, I mean Aikido generally prides itself in being an art that masters the art of ukemi. If they have not mastered the most basic form of ukemi, the breakfall, then I really don't know what to say.
Maybe this is just my opinion, and maybe I am a complete idiot who knows nothing about Aikido, maybe there are secrets that have been kept from me. But in my view there is no excuse for anyone above 4th kyu not to be able to do a breakfall from koshinage with confidence. it is a basic martial arts technique and an art from like Aikido that prides itself in having excellent and graceful ukemi should be ashamed of itself.