Disney was a incredibly unionized shop. The 9 old men where still at Disney (though some had moved to different roles at Disney) at this point, the ink & paint was still at Disney.

You can argue that Disney was stretched way too far during this period due to Disney's grandiose dreams in Florida.

The difference was that Ollie and Frank hadn't bothered to write The Illusion of Life or tried to pass on their skills yet.

If you want to write evils of anti-union Disney, go a few decades earlier to the late 30s and early 40s and the strike.

"were". Not "where".

Is there a longer story somewhere about this decline ?

This piece is not really clear about the reasons _why_ younger talent wasn't being trained on those techniques. If you read the story it seems that everybody was looking forward at people learning and helping them doing so... so why was it not being done at Disney ?

The link only mentions issues with the union, but it doesn't seem to me reasonable to think that it was the only reason.

Organizations can calcify. Experienced people become incumbents, using their knowledge as a competitive advantage. New people don't respect the existing structure. It's half growing pains, half power struggle.

A healthy organization takes these competing forces and integrates them. An unhealthy one (maybe one used to an overbearing, God-like leader?) clamps down, suppresses dissent, and lets the pressure build until something breaks.

The film Waking Sleeping Beauty touches on this a bit.