"What on earth is wrong with our country"
The short answer to that is 'whatever we have allowed to go wrong'.
When people complain about the state of a democratic society they are, in effect complaining about themselves. Our country has become what we made of it. If standards have fallen, it's our fault.
If we want a better society we can have one - we simply need to adopt a higher set of standards and teach them to our children. They will raise the bar still further, and teach their children.
The same principle works in reverse.
We haven't got a better postal service because we are not prepared to pay for one. Royal Mail was wholly or partly in public ownership for over 500 years, but Royal Mail Group Ltd. is a listed company - the government ceased to own any part of it in 2015. Like all businesses, it needs to make a profit for its shareholders,. but that has not proved to be an easy task. The share price is currently bumping along at an all time low. We are not sending letters in anything like the volume we used to, and that has impacted hugely in terms of revenue.
In my opinion, a national Mail service is the one thing that should be a nationalised concern. If America can run a government-owned postal service efficiently, I don't see why we shouldn't be able to do it.