Anyone notice that aikido warm ups have some chi gong like movements or is that just Obata's system?

Not to answer this directly rather to pass on an observation from years of participation and practice in Martial Arts. The study of physiology has been in practice for thousands of years across many cultures. It seems that the more arts I observe closely the more things I see in common. Tai Chi Chi Gong works for fitness, stretching, internal massage, and building stamina. I see similar movements in Hawrang Do work outs. Hawrang Do is the predecessor of Taekwando. I see similarities in Wusho, and Wing Chung Kung fu also. I find this good food for thought.

You'd be surprised at the many similarities in training exercises, we even had some sensitivity and redirection drills which resembled Tai Chi two man push hands drills at our dojo. My Aikido Sensei never even had any Tai Chi background, though he was also a blackbelt in Shotokan before switching to Aikido.

I noticed a lot of similarities between taijiquan & aikido strangely.

I only dabbled a bit in aikido and my jeet kune do sifu was a taiji teacher beck in china and teaches us some stuff since his style is influenced by that.

I want to get further into them to learn more the main differences seem to be terminology from what I can tell lol but I'm really a outsider looking in.