There's nothing explicitly wrong with it, and I didn't suggest that there was.
However, there's a reason that people love to work with some languages more than others. You'll note that interpolation doesn't stop Ruby/JS devs from appending strings. It's just far shorter and arguably easier to visually parse. In short, it's a nicer syntax and doesn't break with any pre-existing conventions or language style opinions.
Believe it or not, C didn't support strings when it came out. You worked with arrays of characters. There's nothing inherently bad about doing that, but working with strings makes some developers happy. Go figure. There are still many subsets or limited instruction dialects that work with arrays of chars today, most notably the GSM interface layer that runs on your SIM card.
