People don't get angry because you tell them there's a high survival rate for kids and young adults.

People get angry because the people who do say that tend to do so in the belief that this number somehow proves that COVID-19 is harmless and that other numbers don't matter, and that is false.

Two main things to keep in mind is that a) death is not the only thing bad that can happen, and b) fatality rate is very high (5%-10%) in diagnosed people with preexisting conditions, in particular cardiovascular diseases.
A quarter of the US population has one preexisting condition or more.

Fatality rate is also much higher in regions with bad healthcare. Lots of people only survive because we can get them the help they need, lowering fatality stats. In other places, that is not the case.

Also, death is not the only bad thing that can happen. Many people suffer from long term effects, and we don't even know the full extent of that yet.