"it is difficult to get a man to understand something when his salary depends on his not understanding it."
If you're the incumbent, a paradigm shift usually forces you to intentionally cannibalize your existing revenue base in service of the not-yet-proven new thing. That's if you want to survive.
It's incredibly difficult, rare, nearly impossible, to pull such a thing off within a company system.
Imagine being Blockbuster, knowing that to survive, you'd need to transition to a content streaming company.
That's a ton to unwind before you can even buy servers, let alone hire the people to -lead the industry- in such a shift. All to simply remain alive.