Telegram has no option for "Only allow contacts to message me", it turns out.
After lots of messages, they eventually offer to auto archive and mute people not on your contacts, but it's still fairly visible on the app.
Perhaps Telegram should work on better abuse management before adding voice chat! I used to love the app but now I am considering uninstalling.
You can't reject images from non-contacts either. It's either images from everyone or nobody.
Does your chats list get filled up with these unsolicited messages from randos?
It seems like they should at the very least offer a mechanism to accept a contact request before any messages can be sent.
It's also an interesting example in the vastly different experience that different demographics can have in an app - say, women, or minorities often the recipients of abuse - and how blind an app maker can be to that experience if it's not intentionally studied.
It was, then telegram desktop popped up with "it appears you are getting a lot of messages, would you like to automatically mute + archive those not in your contacts" or somesuch. Still, the archived folder is at the top
The only thing that stopped it was deleting my message from the community. Guess I won't be participating again :(
It certainly is an interesting example - I know nothing of their team, however things like this are also another reason as to why a diverse team is important!
Maybe even easier is pressing and long holding the name of someone who has sent you a message. In the vertical dots menu is then an option to block the user.
I'm running v7.1.3 from F-Droid.
I do agree though that an option to block direct messages from those not in my Contacts, or at least some kind of review process to allow a specific message from someone not in Contacts, could be a nice addition.
The hold + three dots thing isn't there on iOS sadly.
Even something like Instagram's message requests would be a welcome addition!