There's no avenue on Steemit to send private or direct messages, unlike what we see with other platforms.

Yes, this is a very important issue for Steemit, but I hope that in the future Steemit's team will look into this issue and provide us with the best possible website.

if you lose your steemit keys or password, they can't be recovered.

Yes, if we lose our account keys it will be impossible to retrieve your account as Steemit is a decentralized social media platform. So, don't lose your account keys and store them in a safe place.