Osensei himself said his aikido would die with him and that his students' mission was to spread the art of aikido through the world. I dont think he was actually all that hung up on making people be like him, and he clearly changed his spiel over time as he grew and developed. His reasons were not his deshis' reasons are not my reasons are not your reasons. Are you sure you're not projecting and using the projection as a springboard for judgement?
Oh, you are creating the problem of the ham sandwich with your highly flexible use of the word power. Hmmm, I have some nice black forest in the fridge. Too bad I am out of cheese.
If it died with him than what were they spreading?
Seriously, though, one-line out-takes can be kind of tricky. Of course, reasons vary - I'm sure that, somewhere, sometime, there are people who become Navy Seals as part of a fitness regimen (I actually knew someone who considered this) - but that doesn't mean that is true is a general case, or that it's impossible to state that people have other reasons as a general rule.
A number of people seem to think that IP is about power struggles with other people - but my experience is that there is far less of that than there is in conventional Aikido.