Hello,
The current stable version of phpdocx only supports rsaFull as cryptProviderType.
Please note that the cryptProviderType (rsaAES or rsaFull) depends on the DOCX editor. Some versions of MS Word (such as MS Word 2010) use rsaFull and others use rsaAES when saving a protected DOCX. phpdocx uses rsaFull as cryptProviderType to protect documents. Many other DOCX editors and OOXML libraries use rsaFull as well.
The removeProtection method (https://www.phpdocx.com/api-documentation/cryptophpdocx/remove-password-protection-Word-document-with-PHP) handles both types (rsaAES or rsaFull) because the documentProtection tag is removed when creating the new DOCX output.
Regards.