It still represents a serious security risk, as if that notebook falls into the hands of someone they will have the keys to the kingdom so to speak
So, be it.
Much of life is a trade off between competing needs. Most of all,
@maflynn, I will not let my life be ruled by fear. There are intelligent precautions, and there is paranoia. My paper diary is here beside my desk in my study at home, or in my briefcase, or sometimes in my inside jacket pocket.
In any case, when working anywhere other than in a university, I tend to have two diaries, a work one, and a private one. The work one holds reminders of meetings, times and venues. And that's it.
And, at the end of the day, one can always put a paper diary to the flames, whereas removing, or securing, - or remembering the details of - online storage might prove more troublesome.
And, I am a huge fan of pen and paper - all notes I make at meetings, or for presentations I give, start out on pen and paper. For that matter,
@Apple fanboy - not only am I old skool re matters such as online diaries - I don't, for example, have a smart phone, and while my antique Nokia is starting to stutter a bit, it remains wonderfully unhackable.