I agree, the ship sailed a long time ago. I have been archiving my emails since the 90s. Sometime around 2010 all the remotely loading emails came along, and since then I've several times gone back to look at an invite or announcement and find nothing but an html tag. I guess an archiver that would need print all my emails to a pdf or image file to preserve it, like the emails that show up in litigation. The tools I was using, gmvault or google's takeout, aren't made for this path we're on.

I'm commenting on this way way too late for anybody to read it except for jasonfarnon, but:

Doesn't gmail prefetch / proxy img srcs, in order to not give away tracking/open information to the sender? Or is that something they did a while back but then turned off... Anyway, it would be so lovely when you do a takeout of your gmail data, if they could give you both the original and also a version that had the src rewritten to either a base64-encoded copy of the image or a local file that's included in the takeout dump.