Sorry, but I don't think mail is going anywhere for a long time. The USPS, despite what many say, has done a great job keeping up with the times. They're modernized, and made things easier.
One of those things is Amazon, of course. If it weren't for USPS, we wouldn't be able to get superfast prime deliveries from Amazon. And then there's stamps. I have nieces and nephews and a grandma who all like getting cards in the mail. So it's nice to know you can order stamps online and have them delivered for like, nothing.
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“USPS has done a great job keeping up with the times.”