Over the last 25 years there have been various attempts to tape record speakers but nothing seems to get off the ground.

No resources or volunteers have emerged for
transcribing lectures.

Quite a few of the more serious talks are delivered from a script, and are probably on their way to becoming books, or papers in the
IOM Natural History & Antiquarian Society Proceedings or indeed Family History Society Journal.

If there is a particular past lecture of interest, post up the title and speaker and see whether it has appeared anywhere yet.