Yes, people have been sued before for giving advice that was acted upon.
I remember hearing about an construction engineer who was sued for giving bad advice whilst drunk to a farmer over fixing a dam. The dam failed and the engineer was found to be liable.
I can see the reasonning behind the case, as the engineer has plausible expertise in the domain and could credibly give actionable advice.
When it comes to lawyers, there is already a legal framework where lawyers are responsible when giving legal advice, even when it's not toward their clients, the same way medical professionals have specific liabilities regarding the medical acts they can perfom.
Non lawyers giving legal advice doesn't fit that framing, except if they explicitely pose as one. I'd also exclude malicious intent, as whatever the circumstances, if it can be proven and results in actual harm there's probably no escape for the perpetrator.
That’s possible because the engineer is licensed. A random guy giving bad advice and failing to disclose he’s not an engineer would do no such thing (so long as he didn’t suggest he was an engineer).
I remember hearing about an construction engineer who was sued for giving bad advice whilst drunk to a farmer over fixing a dam. The dam failed and the engineer was found to be liable.