OP less deadly as in fewer people die overall? Isn't that what the restrictions are about? Ie if fewer people die it will mean that the restrictions worked?
There have been far fewer deaths from Ebola than other diseases but it remains a deadly disease, and very contagious.
Rather than compare it with flu, consider COVID 19 as a stand alone disease, like Ebola, say. When severe, your lungs fill with fluid/blood. It might affect your heart, kidneys, liver. If you recover you may suffer permanent damage to your organs.
It is more catching than flu - it has a higher R0 value.
I really don't want anyone to catch this disease. Do you?
How serious your symptoms will depend on your immunity, linked to your age and health, but equally, it also depends on viral load is how I understand it - in a crowded bar where people are chatting for hours, it is more likely you'd get it. In a call centre crowded with people talking you are more likely to get it. On a plane. At soft play. Etc. Many, many people have weaknesses that don't usually affect day to day life - such as asthma.
Sweden - slower to introduce measures, but more measures on the way.
Immunity - Prof Kim Woo Ju in Korea has said that the position isn't clear as patients have recovered, tested negative and then tested positive again.
There is a huge amount of scientific research and data available,if you look for it, and some very intelligent and humane doctors and scientists who have summarised their experiences and research in simple layman's terms. But we are on month 3. Fingers crossed restrictions will work, and the virus will mutate to something less virulent. Fingers crossed. But I would say caution and restrictions are appropriate at this stage.