I'm not sure if you're serious or not, but just because you - probably a young and rather healthy person (my asumptions may be wrong, in which case I apologise) - only had mild symptoms doesnt mean this virus isnt to be taken seriously.
People with pre-existing conditions and/or of old age might have a very, very different experience.
Furthermore the virus can be transmitted directly from human to human - considering that it develops in your throat, coughing or even spitting some out is very likely. Thats why social distancing is so important: To lower the chance that you get infected by someone else or that you infect someone else (please tell me that you stayed away from people as much as possible for at least 14 days and not only for the 4 days you had symptoms... you can transmit the virus even when you dont show any symptoms...) Looking at West Nile virus: Thats transmitted through gnats - so social distancing would do nothing, other methods probably will and those will probably be taken in areas where there are gnats that are know to transmit the virus.
Lastly: We dont have a (curative) treatment or vaccine for Covid-19 - and yes, we dont have one for West Nile either, but as I could hopefully make clear: Its a lot easier for Covid-19 to spread through an entire population thats cuddling in public transport, offices, schools, restaurants, parks etc.
Hospitals in most countries arent prepared for everyone to get sick and in need of a hospital bed - even if only a fraction of people will need a hospital bed and help breathing, the hospitals are not prepared.
You got lucky. Grats.
Others werent so lucky. As of right now 2.673 people in germany were unlucky enough to die because of the virus - and afaik germany only counts the deaths directly linked to the virus, not those were someone with a tone of pre-existing conditions that probably would have killed them in the next few weeks AND caught the virus on top died.
Globally over 100.000 people died because of Covid-19 - not everyone only has mild symptoms.
You got lucky.