I am sorry for the offtopic, but how a number of CS experts who authored the article could get text kerning so wrong in the PDF? Or is it a scan of some paper source?
Seems to depend on the PDF viewer (font issues?). The kerning is almost unreadably bad in macOS's PDF viewer (Preview), but looks perfectly fine in Firefox's built-in PDF viewer on the same machine.
I do apologise, looks perfect in Acrobat Reader.
What makes you think CS experts know or care about text rendering?
One of the great CS experts created one of the great text rendering and layout systems, TeX.
Weren’t the authors of that paper from the business school?