Do academics/researchers benefit from permanent access to conference paper abstracts? Generally, abstracts for papers to be presented at conferences are published, prior to and during such conferences, in online and printed program books. However, in many cases, such abstracts are no longer available after the meeting is over. Would academics/researchers benefit from permanent access to conference paper abstracts?
There's a huge range of conference formats.  At one extreme are conferences at which presentations are given with an abstract but without any associated paper.  These presentations might be associated with journal papers published at a later date.  At the other extreme are conferences in which every presentation corresponds to a paper in a published conference proceedings volume and those papers will not appear later as journal papers (or perhaps only extended versions of the papers will be published in journals.)  

In cases where there are only abstracts, these abstracts might be published in a printed program of abstracts or (more commonly these days) might just be available on a conference web site.  Some people do cite such abstracts, so it's a generally a good idea to keep them in some permanent form.

As an example, look at the AGU meetings abstract database.  These abstracts describe presentations that were made at AGU meetings, but in many cases the presentation never gets turned into a journal paper.  These abstracts are sometimes cited by other authors.  The AGU has maintained this database over the years.

https://meetings.agu.org/abstract_db/