"I would dare to say that the pandemic could be over by now." Then you need to learn more about pandemics. The point of a lockdown isn't to end a pandemic, the point is to buy time. There are only 3 ways pandemics "end". Viruses need their hosts, so most often pandemics "end" when viruses mutate to become less deadly. Modern medicine has also let vaccines be an alternative way to reduce virus fatalities to acceptable levels. Lastly, there's natural selection and only people who have natural immunity survive, but no one wants that.

A more severe and diligent lockdown wouldn't have accelerated vaccine development, and it wouldn't have removed the virus from existing, but it would have actually slowed the mutation of the virus. I don't know what flawed logic you are using to lead you to believe that a more authoritarian lockdown could have ended the pandemic early. 

It's also bad logic to assume a virus that targeted children would have been handled less divisively. Do you remember before Covid-19? Anti-vax parents kept losing kids and it wasn't changing their minds. We live in a world of disinformation. If Covid targeted kids, anti-vax people would be fear mongering that the government and vaccines are killing kids.

You seem to think the problem is that the people "in-charge" didn't have enough power and authority. Look at China, you would think their authoritarian system would actually be good in pandemic situations because they could just blockade entire cities in and whatnot... But China instead cared more about prestige and in the early days of Covid tried to make people believe the virus didn't even exist. This is another reason why your line of thinking is detached from reality. You think giving more power to the people in charge would solve your problems ignoring the possibility that it isn't the system that's flawed but instead the components. Let's not forget who the US president at the time of the outbreak. You really think harsher action from politicians would have lead to a better outcome?