I don’t know all the technical details of attachment size limits on emails. I assume it’s complicated. Any given email server might put hard-caps on what it accepts within the email itself. For example, in 2009, Gmail increase the limit it could send to 25 MB and mentioned at the time:
“you may not be able to send larger attachments to contacts who use other email services with smaller attachment limits“
Twelve years later, that limit is still 25 MB for in-email attachments, so it seems like the email ecosystem hasn’t scaled that up much.
What has changed is the work-arounds. As much anyone might have feelings about whether email is the appropriate mechanism for file sharing, files are a part of modern communication and because email still excels at modern communication, files come along for the ride.
So, companies that offer email as part of how their services, have made sending attachments, especially of large size, much easier.
Apple has Mail Drop, which supports up to 5 GB attachments. You don’t have to think about it, it just works by tossing your file into your iCloud (until you go over the 1B limit, god bless you), and the file “expires” in 30 days.
Gmail has a thing where large files are also auto-cloud-uploaded to Google Drive, and then explicitly shared with the recipients of the email.
I’ll pretty commonly use some cloud uploader tool to get around actually attaching big files to email as well, like I might chuck a .zip file on Droplr or something, which not only makes the email smaller, but I can control if it gets deleted, and has a better chance of making it through a spam/content blocker.
I love these kind of things. They take a gnarly friction point and smooth it over. That’s what tech is supposed to do.