Random thoughts.

Theory X is very convenient for those in charge. No need to think hard - just pull out the whip.

In my experience it takes very little application of Theory X to create enough resentment (even if hidden) to make highly creative work impossible. If you want people to do creative work, Theory Y is your best approach.

Those with executive function challenges like ADHD gain increased executive function if doing what they should is also pleasurable. It takes a long time to recondition such people to this, but Theory Y does so. That said, in the short term Theory X may work better. But the long term matters more.

Some of the best advice that I know for moving an organization towards Theory Y is in Tribal Leadership, https://www.amazon.com/Tribal-Leadership-Leveraging-Thriving....

One of my personal favorites is Tribal Leadership: https://www.amazon.com/Tribal-Leadership-Leveraging-Thriving...