I think the thing to remember is that modern DSLRs are going to continue to produce decent images across challenging lighting conditions. A DSLR buys you more usable shots to select from later.

You are correct, On a sunny day both types of device will produce similar looking 1000 pixel wide web-ready exterior landscape shots. Now take them into a dark cathedral with high stained-glass windows, try for a quick portrait of a priest walking by holding a candle, and the DSLR will still get the shot, and it will look great. Smartphones cannot do this...yet.