Acrobat Pro’s category of Image Object would appear to be limited to raster images: images formed from collections of vectors are something else, apparently undefined as far as Acrobat is concerned. For many versions, now right-clicking with Acrobat Pro’s Edit Object tool has been able to show the metadata for individual raster images, while vector images lack “object-level metadata” even though the vector images are included as distinct “object streams” within the PDF structure, the same category as raster images. Acrobat Pro’s Edit Object can select individual vectors, and with shift-click can collect several, but vector images seems to lose their original integrity.
For a while I have been using Adobe Illustrator CS6 to apply various categories of metadata, including Title and Description, to charts and diagrams before inserting them in ID, hoping that when PDF 2.0 arrives it will allow object-level metadata for vector images. A while ago I stumbled upon the “-ee” parameter for Phil Harvey’s wonderful ExifTool, allowing display of metadata in embedded objects. Lo and behold, sample PDFs yielded the Title and Description embedded in the AI artwork. Clearly, ID has been passing the information along. Perhaps Acrobat Pro simply disaggregates vector objects; hopefully other professional tools (from Callas, Enfocus, iText. others?) handle this better.
As for PDF 2.0, over on InDesign’s Acrobat forum, Dov Isaacs suggested on October 7th that PDF 2.0 support will not become mainstream before the second half of 2020:
https://community.adobe.com/t5/Acrobat/Acrobat-Pro-DC-create-PDF-2-0/td-p/10654727
David