It's basically a synonym for invited. Or from a dictionary: "asked or invited to do, provide, or contribute to something". Unsolicited is the opposite.
If you send someone an invite to a discussion, they're invited, whether you meant to or not. At least long enough to send a single reply (which may be multiple tweets).
Whether their response is a polite "you tagged the wrong person" or some awful screed does not change whether a solicitation happened. Especially because tagging someone is not a request for any specific sort of reply.
Relatedly, if someone is eavesdropping in public and steps into a conversation to make the most wonderful helpful and loved comment in the world, doing that was still unsolicited.
I disagree completely. If you got a wedding invite to your address and name but you _knew_ it was intended for a person of the same name and similar address.. would you argue that you had a right to go to the wedding by the fact that you received an invite? Yes, it would be helpful for you to notify the sender that you got it by mistake but it doesn't mean you're invited and your message back to the sender wasn't requested because the whole thing happened by mistake.
Also tagging does not necessarily request a reply at all.
This is silly and will go in circles so I will finish by just saying.. What the fuck did you just fucking say about me, you little bitch? ....
If you send someone an invite to a discussion, they're invited, whether you meant to or not. At least long enough to send a single reply (which may be multiple tweets).
Whether their response is a polite "you tagged the wrong person" or some awful screed does not change whether a solicitation happened. Especially because tagging someone is not a request for any specific sort of reply.
Relatedly, if someone is eavesdropping in public and steps into a conversation to make the most wonderful helpful and loved comment in the world, doing that was still unsolicited.