this can’t be real
Have you ever worked in academia? This kind of email could definitely be real, not saying this one necessarily is though
I have never worked in academia, but I’ve spent time around academics and have read plenty of emails in both academic and corporate contexts … this particular one looks fake, even if the circumstances of plagiarism are common - this just not seem like how a thesis adviser would address this kind of plagiarism with a grad student
Sounds like you would be shocked by the reality if the situation.