I believe from iPhone 6S and above, there's an option to just say "Hey, Siri" to activate Siri without having to touch the phone, so you can basically do the same thing with iPhones.
Also, your phone may be deep in a pocket, in a coat, or in your purse in the other room. Echo/Home is right there in the kitchen waiting for you.
Lastly, you have no battery worries. Want 12+ hours of music in the kitchen? No problem.