Earlier quoted context omitted.
Thats not true. The reddit thread explicitly states what he wants to do is legally and ethically problematic. And it spells out why. "That is why the functionality doesn exist in exhcange" was the sort of end result of the larger logic here.
Yes the thread says that, but they are wrong. No lawyer in the world thinks that Microsoft Exchange is some sort of legal chain of custody or inviolable vault of perfect information. The reason Exchange does not have the functionality to redact email address is that people who need to redact information usually prefer to do it by hand, so it would be a waste of Microsoft's time to build a utility to do it. But to thi…
As a business person, nobody would [buy/use] exchange if it was not reasonably secure from an audit trail perspective. The intergrity of the communications is required for many business's who have record retention policy and what not.
Think about an analogy for a bank's accounting system that allowed audit trails to be compromised. Its a huge problem for the purchasing people and the managerial layer that has to sign off on sarbox etc.