Why is this deprecated?
Since 6.0, HTL should be used to develop components. HTL and SlingModels provide better facilities for achieving the same functionality provided in ComponentHelper, thus it is deprecated.
Provide a simple abstraction for creating CQ-specific markup that drive component-based authoring elements like drop-targets and placeholder icons.
The most common use case of the ComponentHelper is to control the execution of a component JSP based on it configured status.