Personally I like the TnA
No worse than non-cable TV imo.
I don't have Cable or anything but I recently say an advertisement on Nickalodeon promoting their NYE special to children and there was a crazy amount of TnA. The worlds view on acceptance of TnA is changing I can't see fighting the changes as working but as a compromise I will be more aware of what I post.

Maybe Pinside needs a children mode, though that sounds like a huge headache to implement

18+?
Way to high imo, at 18 you can smoke and join the army.

Have you see a PG 13 movie lately? Way heavier than Pinside.

Instead of taking away adult content (non of which is R-rated), I vote for a junior pinhead mode…
If your child has access to pinside you could have their computer auto login in and they would only have access to Tech sub forums, playing tips, maybe add a special area for them etc…those usually stay pretty clean. It could also hide anything with a tilt. And maybe when someone opens a thread in the forum there's a note at top that indicates it's junior pinsider accessible thread, reminding them to keep that in mind.
While it's not what you're going after 100% I think it's a pretty nice compromise.
Any thoughts?

He's the OP and an official pinball wizard