I think you are very wise to have titled your question as you did. It really is just a question of how you define "personal." Also, it depends what you're comparing it to -- less personal than what? Writing letters? Sleeping together? Marching into the complaint desk with a faulty appliance in your hand? Seeing each other once a year at family weddings and funerals?
Personal = intimate? I have had some very "personal" conversations by phone and e-mail. But the statement seems to imply that back in the good old days when you had to travel to another city to see someone and talk in person, there was a more desirable level of intimacy. I disagree. I think it is nice to be able to keep in touch with friends without being in the same room. For example, soldiers at war, or children away at college, or sweethearts separated by work assignments, can share their experiences and stay up to date with loved ones every day.
Personal = you know the identity of the person you're communicating with?? In this case I'd agree. I talk to many shop clerks, government officials, office assistants, AnswerBank posters, etc on the phone or by internet without knowing anything about them -- their name, gender, level of integrity or honesty, after-work habits, etc. It is easier to remain anonymous by phone or e-mail than face-to-face. But really, how much would you learn about the lady at the city hall information desk if you wrote her a letter?
Personal = the opposite of business related?
Personal = you take responsibility for your statements?
Personal = based on your looks or other attributes, rather than the way you wish to present yourself?
There are many ways to interpret the question, & to answer it!