Normally I'd agree with you, but trust me, outlaw isn't worth the time and effort.

But why do we need to gain a deeper understanding of her private life? We know about the amazing things she did (especially for my community) and we can appreciate her for that. We don't need to expose absolutely everything about her. It doesn't change anything, and I very much doubt she would have wanted such private and personal recordings to be released to public scrutiny.

There have been countless books on her so I don't believe there could be too much shocking footage there to really be concerned about.

If there's no new information to be learnt then what's the point of releasing the recordings? Let it lie, and use the vast amount of resources already present to form a judgement on what her private life was like.

Let's focus at first on Diana herself.

From what we know, Diana was a woman who fiercely valued the privacy of her personal life and the personal lives of her children, despite her position. Judging by her character, and not whether it's morally acceptable to release private recordings of any dead person in the first place, do you really believe she would appreciate having such things broadcast for all to see/hear? I think it's pretty obvious that she wouldn't.

Now, onto the more broad matter: is it moral to broadcast the private recordings of a dead person, whoever they are? I'd say it's completely subjective, down to the person's character and the nature of the recordings. It's also a matter of whether the family believes it's for the best.

So, overall:

For Diana? No, and I even think it's morally reprehensible.

For any deceased person? It's completely subjective.