Re: Should've posted this earlier
'They might've deleted it or something - it was 200mb or so, back when that was still "big".'
It may have never arrived. Back in "those days" oversize mail often went down a black hole instead of generating NDNs.
One of my earlier experiences as an ISP was dealing with a government department (NZ's version of the DVLA) who were attempting to _email_ databases to consultants in another city, on another ISP.
About 250MB, over a 14k4 dialup modem, transfers initiated at end-of-day (5pm)
This was back in the days of sendmail 9.6 or lower and when the default (almost universal) mail limit was 10MB, but size only got checked AFTER the message was received. It didn't help that the /tmp/ area the mailserver used for buffering incoming messages only had about 100Mb of allocated disk space (this was the days when 1Gb cost £1000).
After several hours grunting away trying to send the message, our mailserver would choke and crash. It took a while to nail what was causing it (SunOs wasn't helpful in that respect) and when we increased the space, error messages about the oversized mail started being issued.
The "head of IT" at the govt department made out that it was all our fault that they couldn't send these dumps to their consultants, never mind that the other ISP also had a 10Mb mail limit (he was the one who'd had the bright idea of emailing it, claimed that he knew mailsystems backwards and that none of them had size limits)
Some years afterwards he showed up at another customer (a large clothing distributor) where thankfully the IT staff knew of his past and managed to get management to keep him on a short leash. He didn't last long there, but apparently that was down to being caught downloading porn on company equipment rather than technical reasons.
FWIW: That 10Mb per message default limit is still in sendmail and most other MTAs. ISPs often set the limit to a lower value, but at least these days when the ESMTP handshake takes place and the client side says "I have a message of N size", the server side will say "No, too big!" BEFORE the message is transmitted.