All of these are very reasonable by me.
Don’t get me wrong, I also love the pipe operator, it’s just that many people love to get creative turning everything they can into a “pipeline.” It’s maddening as “looks cool” but doesn’t help with readability or debugging. I’ve also run into several instances over the years where it makes changing code really hard because all the code was tailored to work with pipes that didn’t lend well to changing steps in between (at least not in a sensible way).
I’ve said this a lot in the past but the small surface area of Elixir is very expressive where the constructs you use can communicate a lot about the code (“the medium is the message” if you will). For example, if I see with I think, “multiple side effects.” If I see a pipline, I think “effect-free data transformation that always comes out the other side.” I’ve found that whenever you find a pipe naturally breaking, it’s almost always means that it’s a good place to break it and assign it to a variable. This is especially true when see folks adding comments as to what the data looks likes like at this point.
There are a whole bunch of other things along these lines. Like piping into elem when you know its length is never better than pattern matching, I consider then and tap mostly evil (they are useful for debugging albeit pretty much just useful for debugging nasty pipelines), and don’t me started on |> Kenerl.+.
I do agree it gets murky with the raw value thing and “no single pipe.” For me it comes down to taste and it’s hard to describe and I don’t get too hung up about. For instance I also don’t like x |> Foo(), though in a changeset I will often do:
foo
|> cast(attrs, [:bar, :baz])
because there is often going to be more coming and makes for nicer diffs. I dunno, again, it’s more to taste and doesn’t really hinder readability/changeability in any meaningful way.
Of course it all comes down to taste, but I’ve come across a lot of production code that is full of “pipelines” that contains multiple different data-structures and multiple side-effects. It’s in these extreme, and unfortunately common, cases I say “to heck with your art” (or just type “LGTM” and hit “Approve”).
But I also haven’t used too many languages professionally. Ultimately, is what it is 
