The quality of export is dictated by the quality of the PDF.
We are talking about the "inner essences" of the PDF (e.g., degree of compliance with the PDF Standard - ISO 32000-1).
So, what goes in goes out or "GIGO".
This has nothing to do with Acrobat, Acrobat's export process or the online subscription service that exports PDF page content.
A well-formed Tagged PDF (compliant to ISO 32000-1 & ISO 14289-1, PDF/UA-1) provides a PDF that proactively supports content export by Acrobat.
After all the "design function" of tagged PDF is to faciliate have not only accessible PDF but the export/repurpose of PDF content (yep, that's what the ISO standard tells us; as does the PDF References that came before ISO 32000).
To get the good stuff from export you start with a well-formed Tagged PDF.
Goodstuff In — Goodstuff Out
or
Garbage In — Garbage Out
"GIGO"
The core of PDF has no word processer, spreadsheet, or page layout functionality/information.
See ISO 32000. (So, back in the Age of Titans Adobe provided PDF with logical hierarchy and then tagged PDF.)
Read the article "Each PDF Page Is a Painting"
http://talkingpdf.org/each-pdf-page-is-a-painting/
This article can give you an appreciation for what the base PDF is.
Be well...
