How about some computational task where coding only the happy path means accurate calculated results for 80% of the cases?
I think my problem is the marketing hype with Elixir around "happy path" and "self healing" are too broad and resemble hype more than feature description. I'd be happy if those terms weren't used outside of marketing literature, until we have an AGI that can manage complexity on its own :)
I just gave an example of how happy path programming works in a use case that is pretty common to my day to day. A lot of other stuff I do is similar enough that the same applies, and that's just my experience, not marketing hype.
Some articles might be a little over-excited, but I don't think I've generally read articles that claim Elixir is God's gift to programmers ;). And in situations where Elixir does help, it can be very exciting.
FWIW, I wasn't aware that Elixir is not optimal for CPU-bound tasks. I use Go for highly concurrent servers, but it uses goroutines not a process per request, and mutexes and/or persistent channels to synchronize shared memory access.