This surprises me. I've never heard of anyone losing an internship or co-op position for such a reason. I can't think of it happening anywhere I've worked. As both of us have anecdotes however, perhaps some data on this could be enlightening.
It happened to me at Berkeley in 2005…the seeds were already being sown back then. I only found out years later that I was rejected for being in an apparently inappropriate facebook group. Someone on the committee was offended and that was that.
What was the Facebook group? "Apparently inappropriate" is too vague to know what the problem was!
I don’t want to be cancelled again so I won’t share specifics but think south park level humor