Ethical? I can’t see how it would be ethical or unethical to send a message to someone at a company with whom you’re interviewing, unless the message itself constitutes an ethical violation. But I assume you aren’t trying to send Bitcoin bribes or links to malware so can blackmail your way into the job.

That said, cold-call messaging a prospective employer probably won’t help you much unless you invest in personalizing the message and give the recipient a reason to care. And you’re probably better off messaging the hiring manager than a managing partner—executives don’t usually micromanage intern hiring.

In all likelihood, you’ll get or not get an offer on the strength of your interview. Good luck!