I don't even need to argue that certain public officials should not be permitted to have privacy while in office. She has a right to privacy. I am not arguing she doesn't.
I am arguing she made a series of poor choices that led to a situation where the only way she can live up to the standards we should expect from a public official (a verifiable paper trail for business pertaining to office) is by keeping a record of her private communications as well.
This is why you don't use your private email address for official business. If you want privacy while in office you don't use your private email server for official business. You aren't supposed to anyway. It's very simple and very reasonable.
I do NOT demand she hand over personal email! No. Only that she make it possible for a 3rd party to sort her emails into private/public.
She has the right to delete personal email - but only if it's actually personal, and I don't trust her to be the one to decide that.
She brought this on herself by mixing them in the first place. Want to maintain your privacy when you know you job requires publicity? Keep your public and private lives separate. She chose not to.
If a piece of information is stored so that it can be given to someone else later, that's not really very private. Privacy means the right to keep things away from others, and it includes the right to delete things.
Now maybe you want to argue that certain public officials should not permitted to have privacy while they are in office. That's fine, make that argument, but it's not the state of things now, legally or culturally.
And consider that there might be unintended consequences. It might deter some great people from considering public service. And it might put a hole in the legal concept of privacy that others will try to widen later.
I would argue that if we're going to be serious about legally protecting privacy, we need to be consistent. "Protect privacy, except for politicians I don't like" is not a particularly strong legal framework.