The vaccines prevent severe illness and death. Likely also prevent you from spreading it to others.
Around 5% of people infected with COVID-19 require hospitalization. Around 3% end up in the ICU. 0.65% die.
Monoclonal antibody therapy is helping to reduce those numbers to an extent, but that gives a basic idea. The vaccines cut those numbers to zero.
OK thanks...its a complex problem with a complex solution.