Quoting the article: "OTP stands for _Open Telecom Platform_, which is literally a meaningless name that was used to get the stuff open-sourced back in the old days of Erlang at Ericsson."
"The name OTP WAS originally an acronym for Open Telecom Platform, which WAS a branding attempt before Ericsson released Erlang/OTP as open source."
Today, OTP is the name.
To avoid confusions, it would have been best to add "(Erlang)" before the title.