Lockdown? Is this necessary?

Here we are, in Spain, by Royal decree, in lockdown! People are incarcerated, all entertainment including sports are forbidden, businesses are failing and people are watching their dreams and aspiration destroyed on or for what?
A small number of people have died from a virus that has infected many more without harm. Their death hasn't been unduly horrible like for example with ebola. Nobody in authority has volunteered how many people have died of seasonal flu or pneumonia in the same period, all without fanfare or panic. Nobody goes round wearing a face mask against common colds of flu. Coronavirus is a highly contagious but relatively mild illness that can be fatal with those with an underlying medical problem especially those with respiratory concerns. So why have Governments risked the world economy by taking this severe action?  I believe it's because, in this snowflake generation, to be seen to be taking no action, a sentiment fuelled by stupid oppositions, Governments would be penalised at the next polls. It makes a mockery of Democracy if legitimate Governments don't do the right thing for fear of finding disfavour with the electorate.
At times, it is understandable if Nature does its duty of checks and balances on the planet, correcting, for example, climate and population surges. Some remedies (like asteroid strike) will be heavy handed and others (such as coronavirus) a light touch on the tiller.
They should ride this pandemic out, accepting that most people will contract the illness and move on whilst businesses are allowed to continue as normal, earning a profit, employing folk and paying their taxes. Save the dramatics for when the real thing turns up, a highly contagious retrovirus like ebola or a genetically altered, incurable plague.