I am not an Aikido expert. I have had some instruction in Aikido, but more geared as an adjunct to Karate. In fact the source was from someone who trained in Japan in the 1930s.
You hear that the pre-WWII Aikido taught by Usheiba Sensei was more hard style, and the post-WWII Aikido that he taught was different, softer.
An interesting video by the Aiki news folks, seems to put that in a different light.
The techinques Usheiba Sensei showed in 1936 and then in 1951 seem very much the same, and his Aikido did not change appreciably over the years.
I suspect the change was more how students were being trained.
First, let me show some screen prints from that video.
The video is here.