You still have the original vtkCellLinks as one of the available options. The reason for the new design is in the docs (VTK: vtkStaticCellLinksTemplate< TIds > Class Template Reference):
This class is a faster implementation of vtkCellLinks. However, it cannot be incrementally constructed; it is meant to be constructed once (statically) and must be rebuilt if the cells change.
This is a templated implementation for vtkStaticCellLinks. The reason for the templating is to gain performance and reduce memory by using smaller integral types to represent ids. For example, if the maximum id can be represented by an int (as compared to a vtkIdType), it is possible to reduce memory requirements by half and increase performance. This templated class can be used directly; alternatively the non-templated class vtkStaticCellLinks can be used for convenience; although it uses vtkIdType and so will lose some speed and memory advantages.
best,
PC