That's very true! It's not just kids. However (and maybe this is disingenuous) I believe that HN is both more enriching (I learn new things every single time whereas tiktok is mostly mind-numbing videos that no one will remember in six months) and less addictive (relative to something like tiktok). It's still social media, but it really is nothing like tiktok. Ask your kids for their screentime, or ask which of their friends has the highest. I bet it's at least 10 hours, and the likelihood of it being tiktok or instagram is very high.
"more enriching" is how we fool ourselves to continue diverting our attention - speaking for myself - it's just math on youtube, it's just stackoverflow/programming, etc. Unfortunately the cycle of infinite information needs to be throttled I think.
Again, maybe this is just me being disingenuous, but I'd disagree - while your examples may be used as a time sink, I believe there is definitely a difference between scrolling on tiktok, and watching math on youtube. You're probably far more likely to use and improve your brain and its critical thinking skills.