stagnator
Definitions
A person or thing that causes something to stop flowing, developing, or progressing.
One who remains inactive, motionless, or in a state of stagnation.
Examples
The company's refusal to innovate turned its long-time CEO into a professional stagnator.
By resisting all new technology, the department became a stagnator of progress within the firm.
He was labeled a stagnator because he consistently blocked any attempts to modernize the outdated workflow.