Training people is expensive in both cash for the business and the time of those around them
You're definitely supported by an enormous amount of evidence in this.
In my current job, we have a small group of employees with specialties in sciences, medical, hazardous materials, IT, threat/plume modeling, and running daily activities. They go to so much training in their first two years, they're gone all the time, and then they are still almost worthless for another year due to lack of real-world knowledge they couldn't get from these special schools.
When we hire the wrong people, it's a huge problem in costs, lost time, and then it makes finding replacements that much harder and shorts the organization longer as well.
Finding the right people who are a good fit is hard.