you realize the famed 'contact tracing' is basically the phone version of a "freaking voluntary email?" you also realize that there are boatloads of studies, chiefly from south korea, sweden, etc., that show the same thing?
and yeah, do you want to know why some countries don't test asymptomatic people? because it's not a viable nor sustainable strategy that has ever informed public health policy in the history of mankind, particularly with a flawed PCR test. when the H1N1 pandemic hit in 2009, which did actually pose a mortal danger to large swaths of children, we recommended quarantine of....symptomatic people. if your kids are sick, keep them home. if they're not symptomatic, it's very, very likely they're not spreading it (just like the WHO said, which dr. van kerkhove was forced to walk back for no good reason).
"what we're even doing here" is trying to collect data, so that you can't just throw your hands up and say, "TOO DANGEROUS! GUESS I'LL JUST STAY HOME MERRRRRRRR" because the world can't function like that, and only house-bound agoraphobes live that way.