If you want more, from someone else who was there, check out Joe Armstrong's "History of Erlang" paper:

https://dl.acm.org/doi/abs/10.1145/1238844.1238850 -- canonical link and has a video of the related talk (streamable and downloadable).

(Sadly, without ACM membership, the paper itself is paywalled; there are copies of it online though, e.g. https://www.labouseur.com/courses/erlang/history-of-erlang-a... ).