It would take armed press gangs going door-to-door to enforce a draft. Especially when there’s no real national emergency. Even if there was, I doubt anyone would show up as long as the internet and cell service was still working.
Like the 'Slacker Raids' of WWI on Steroids.
So, your cell phone would stop working if you fail to appear, right?
It doesn’t seem unlikely, to me. Millennials don’t know how to live without their smartphones.