The smartphone / social media genie completely upended parenting and expectations even before "remote learning" made them nearly required.

And haven't you ever seen a 2nd-grader with a Deadpool backpack?

The connected world has been difficult to navigate with kids. While I work in IT and generally dislike and distrust nearly all forms of social media.... peer pressure, lazy parents, and pseudo-endorsements from the schools themselves pretty much made it so that every "other" kid had an unsupervised phone by 6th grade (back when my oldest, now 17, was there... so this was like 5 years ago). I'll never forget the time we went to a 4th grade academic team tournament hosted by a nearby elementary school, and the library was plastered with artsy posterboards of various teachers' Instagram and FB profiles and such. Like, HOLY SHIT WTF are you promoting this for?? It wasn't good enough for the adults to get their dopamine jollies via technology, they had to demonstrate this to impressionable elementary kids too??! Bad enough our own school kept encouraging smartphone tools and stupid portals that changed every other year...

...but that horrific library display made me realize the war was lost.

Now, since I had been "that kid" in school whose parents closed him off from everything, which frankly made my life a living hell, I'd already decided to take a more nuanced view of the world and not shelter my kids. THEY KNOW (or THINK they know) MORE THAN YOU WANT TO ADMIT. I went to chaperone a 6th grade band trip and while waiting in the auditorium at 6 am, bunch of kids had their smartphones out playing Pocket Morty's and quoting the show, which my own kids hadn't yet seen.

So I watched it with them to supervise and lend context. And eventually yes, they got phones in middle school, though they were some of the last.

You can't live in a bubble and you can't keep your kids in one. Once they walk out your door and into school IT'S OVER for better and worse. You can only bring context to the world outside those doors. My kids ask tough questions and have known "the meaning of words" since they were little, and I'm fortunate we still have open and frank discussions. We even occasionally swear. But they have never once embarrassed me and in fact, teachers and other parents alike often marvel and ask what me and my wife have done so right?

I'm no expert, so I'm not really sure. The only thing I always tell them is "we adults let the Genie out of the bottle, so we adults have to keep him in check". After all, I thought it would be sooooooo much fun to show my girls silly Cookie Monster videos on YouTube - back in the good ol' days before YT became a cesspool - so of course they wanted to look that up themselves. And finally on a particularly hectic day I said "sure, fine, daddy's proud that you're learning to use a computer". Until one infamous day YT went into that auto-play next-vid bullshit and for some reason added an.... adult bastardization of Cookie Monster.... and I realized I'd fucked up. But in hindsight that's the LEAST of the issues out there today.

I guess what I am saying (venting) in too many words here OP, is I feel your pain and wish you good luck! But it's probably past time to start helping your child put the rest of the world in context, before the world forces him to figure it out himself. And yes, FWIW I don't agree with what his instructor did... BUT that is probably not the last, or only, questionable instruction he'll receive... and far from the worst thing he's seen or heard already.