reminds me of Bill Gates in the 90s when asked about email spam. He said it would make sense to make an email cost like 1 cent so the spammers can't spam as much but this didn't sit right with the mindset of the people at the time.
TLDR: Mail storage is the sender's responsibility. The message isn't copied to the receiver. All the receiver needs is a brief notification that a message is available.
"my2cents"
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