The problem is you're acting as if there is a right and wrong answer to whether there is value to the Echo, when it is completely a personal preference. If you'd rather use your phone to do everything, that's fine with me. Personally, I'd prefer to use the Echo to do certain things. I don't like having my bluetooth turned on on my phone, so if I want to use a bluetooth speaker I'm constantly having to turn it on and connect it. If I want to get a quick update on the weather while I'm fixing my breakfast in the morning, it's easiest to just say, "Alexa, what's the weather". I have multiplex echos/dots throughout the house, so there is one pretty much anywhere I go in the house which is more convenient then making sure I have my phone with me at all times.
My echo can interact with my firetv, so I can tell it to open netflix or playstation vue. I can tell it to pause which is convenient if something is on while I'm in the kitchen and I want to see it. I can just tell it to pause instead of going into the living room and finding the remote and pausing it. Can you do that with siri?