using caching where specified but the pipeline page doesn't show anything at all.

What do you mean by " the pipeline page doesn't show anything at all."? are you running the pipeline ? how ?
Notice PipelineDecorator.component needs to be Top level not nested inside the pipeline logic, like in the original example

@PipelineDecorator.component(
        cache=True,
        name=f'append_string_{x}',
    )