This is incorrect. The initial cursor position and automatic email signature being at the top rather than at the bottom already makes a huge difference. Add to that the absence of tools to easily insert inline replies and cut down or reformat quoted parts, plus the absence of navigational behavior when reading mail that would jump to the first non-quoted part first, which earlier email clients used to have.
Yes, when I had to use Outlook because of $dayjob I did bottom-post and it was absolutely an uphill battle. In the end I resorted to some custom VBScript code I wrote myself to make some aspects easier.
In hindsight, all of that was a mistake because all my coworkers top-posted. Top-posting might be bad (IMHO), but a mixture of bottom and top is even worse.
I now just top-post. I'm still not a fan but it is what it is.
Not sure what you mean, email signatures were standard well before Outlook. What changed is that the convention of beginning them with a line consisting of “-- ” wasn’t adopted by Outlook & friends, so automatic detection/hiding/non-quoting suffers.
I mean that we already have SMTP headers for metadata.
Such as in-reply-to (no need to quote the whole mail at the bottom of yours) and obviously the sender (no need for an explicit signature), and you could use x-face if you needed something fancier or, if your company really really needs to remind everyone how social they are at every message, you could have added an x-coprorate-blurb custom header, etc.
Whatever, emails these days are nothing more than an archaic last resort password reset protocol.
