I've been a corporate marketing VP for much of my career (several hundred million to multi-billion dollar companies) and, as such, have also managed internal and external ad agencies and creative personnel. As long as a portfolio is accessable via the Internet a paper copy has never been a deal breaker. Now when I need concepts delivered that's another story.
Good for you. Next time you have to deal with a city on building out a commercial property, see how far that will get you. Commercial/Interior design firms are required to provide drawings and source code for the drawings, to a city for approval. Or maybe when you sit in on a meeting discussing what materials to use for the flooring, walls, and so on, and see how far that electronic display will impress you.
Try making a display board for a commercial client on an electronic device. And when they ask what the texture of the material is like, you can whip out a sample from your briefcase. Then they will want to know what how reflective and durable the flooring is. And so on and so forth. Walk into that meeting with an eletronic device and you will lose that business. People want to see it and feel it. Interior designers make boards with all the samples on it. This is the best way to win a client.
My Wife is incredbily successful at her job. She knows how to win business. She is one of the most sought after interior designers in the D/FW area. She also loves technology and uses it where it makes sense. Try to get a job with her without a physical portfolio is not ever going to happen.
I stand by my assessment of the iPad. It is a worthless piece of technology that Apple zealots are desparately trying to find a use for. It is a joke.