You may want to take a look on pySetTextExtractionCapabilities which controls document types. This is not limited to OCR component, in other words if you want to retrieve text from docx or xlsx files you may do it.
However if your scenario is that you have in a xlsx document a picture which you want to OCR then it is not supported. OCR component works with images (e.g. jpg) and as a container for images it can process pdf files.