"I feel it would be irresponsible to give my clients digital files as their permanent masters, knowing they would eventually disappear or become unusable, so I won't do it."
The hilarious thing about this is that I don't think anyone even makes analogue tape machines, right now. I checked Fostex, Studer, and Tascam. No tape machines being made.
Given this .. how easy will it be to play an analogue reel to reel tape in a few short years ?
Hell, I currently have no easy means to play my 4-track double speed/dbx cassette multitracks from years ago, and I have to go out of my way if I want to play an LP.
But, I can still access a tar file produced by a machine from 20 years ago, and I'd expect to have no trouble accessing a tar file from 20 years ago. Digital makes it easy to move your data as new technology comes out. Each time you copy your analogue tape you lose some of the original recording.