They make a ton of sense (way more than they do for Erlang) in the context of EEx, which is part of the standard Elixir distribution, and a first class part of the language
Which are you saying is more functional? And why?
Erlang doesn't have a first class pipe macro or special form I don't think, and its standard library isn't built with this in mind, with consistent data-first argument order. So again it's not "less functional" but it doesn't much use one of the most recognizable idioms of functional programming and the only uniquely functional one many people may be familiar with.
I don't know if this is what they meant but it makes sense to me. In elixir piping streams is an ergonomic and similarly performant solution, with the tradeoffs discussed in the article. There's a lot of use case overlap. If the language didn't have comprehensions it wouldn't be very painful for most people, I don't think. Where erlang without them would be a pain in the ass it really has no other general purpose tool for this.