Re: Perhaps the tide is changing.
I think that if you are professional, and make a living from teaching aikido, you have to diversify in order to survive economically. The only dojo I am aware of (in Japan, of course) that does not do this is the Aikikai Hombu, which has a huge population base (Tokyo and its immediate environs, blessed with a very efficient transportation network) and which also is unable to diversify for ideological reasons.
Apart from the Hombu there very few dojos where the instructor is professional. I think there is also another factor here, which has to do with the intellectual and cultural climate of postwar Japan. If people want to practice aikido or judo or kendo, they will go to the appropriate dojo and get on with it. I have met very few Japanese who wander around to various dojos to check on how effective the training is. (In fact the only person who did this was a young Japanese 3rd dan who moved from Tokyo to Hiroshima: I am happy that he chose our dojo out of all the others, which, in fact, is the only one run by foreign instructors.)
I also teach at a dojo in Hiroshima City, where there is a large children's class. There is actually a waiting list, owing to lack of space. The main instructors are an 'aikido' family, where all the members are yudansha (from 6th dan downwards: I have been friends since I first came to Japan and watched the family members grow up).
I can see that the kids come to the dojo (their parents sometimes train in the adult class) because there is a very important element of social training, which, I suspect, is considered increasingly unavailable in the Japanese school system. Some of the kids are older, but entered the dojo when they were six, which is the minimum age.
I wonder how common this is in the US.