If-expressions is a specialized version that only works on booleans, pattern matching is a more general concept (that of course can be used to implement if-expressions, but so can pure lambda calculus)
I did not mean to imply that there are no if blocks in Erlang/Elixir. Just that I use them a whole lot less. Probably an order of magnitude less.
And you still have to decide where your code goes at some level. The pattern of having two function variants (one which matches an empty list, and one the head/tail) is a different idiom to looping. So while for loops go away, you still traverse sequences. And more generally, a lot of the if(else) clauses I would normally write, now get solved with pattern matching.
With control flow languages, the where the code goes and what the code does feel very intertwined, whereas with the pattern matching idioms, I find that where it goes, and what it does, are more orthogonally declared.
