It's no longer considered a correct acronym as erlang is not really a telecoms language anymore. It's been a problem where outsiders are quick to think or say, "I am not writing a telecoms app" and dismiss it.
I understand this reasoning. The conclusion I draw is that "OTP" is truly a miserable name — like "car cdr" level bad.
As a newcomer to Elixir's OTP, I cannot divine that experts hold the opinion that the acronym expansion is misleading when that information is deliberately withheld. The first thing this article did was send me off to search the web.
Folks should use a backronym, like "Opinionated Threading Platform".
Gotta love an introductory article on "OTP" which even includes a section entitled "What is OTP?" but doesn't expand the acronym.