No. Although PDF invoices are sent and received digitally, they are only an image of the invoice. In other words, an image of the paper version. Incidentally, this also includes invoices in .tif, .jpeg and .docx formats. These are not sufficient for automatic and electronic processing. This is because in order to process PDF invoices, for example, the invoice data must be transferred to the accounting software manually or via additional systems (e.g. OCR).
The e-invoice, on the other hand, is an invoice issued in accordance with the EU standard in structured format (XML format), which allows automatic and electronic processing without media breaks. Invoice data can be read out directly and without media usage. Have you ever seen an e-invoice? These are not primarily intended to be decodable by humans (although special software can make this possible). Rather, the purpose of the XML format is machine readout.