People who don't care about your shit expect not to send or receive emails, just easy to digest posts in an infinite timeline while they're on the toilet.

But people who care about what you have to send them (e.g. your grandma when you send her pictures of you and your boyfriend on vacation, your dad when you send him pictures of his grandchildren, a close friend when you tell her about your new job) are very happy to receive what you have to send to them and reply to it, no matter the medium.

Yes, if you want to address 99% of your social network email is probably not as good as Facebook, but if you only care about the 10% that's closest to you, the technology doesn't matter. One of my best friends from high school still sends me paper letters, and I am ecstatic to receive them when I do.