Look.... I believe in democracy, but I don't have a religious fervor over it. I am shocked when my fellow Americans seem so unschooled in basic history. Indeed, many of the undemocratic things put into our constitution (like the much maligned electoral college) were put there by our founders hoping to avoid the pitfalls of democracy. They were very aware that democracy typically fails spectacularly, and put in many anti-democratic things into the constitution to avoid it.
Contrary to that England is a parliamentary democracy for nearly 200 years now and the monarch only has a representative role.
But on that account every form of governance has failed. How many autocracies and monarchies have failed? In that case it isn't because of fundamental flaws and had other reasons?
I don't think the US constitution is full of anti-democratic rules at all. On the contrary, its intent is to grant rights.
People make statements like this and I can only hope they're not american, because the idea you could be educated in an american school and come out believing this is too horrifying to ponder.
Our founders directly stated in contemporaneous documents their fear of unchecked democracy and how it can descend into tyranny.
There is a natural conflict between democracy (and any form of government) and individual rights.
The founders sought to create a republic (not even a democracy really) with heavy protections for individual rights which they saw as at risk from democratic forces
That you think individual rights and democracy are intertwined is only because of bad history linking the american constitution to some great creation story of democracy itself. Many democracies have been authoritarian nightmares for those in the minority
Some Americans wanted a monarchy after the civil war, but they still wanted individual rights protected. Democracy won out but not because of its human rights record. Indeed, the founders were familiar with democratic tyranny based on their classical studies.
The examples of the natural misalignment between democracy and human rights are numerous. Slavery, Jim crow laws, drug laws, all of which were highly popular in their day or are popular now, but agree or disagree obviously curtail individual rights.
Now to your points.... No the Roman republic was not at all like north Korea. The Roman republic was an actual republic, with elections, power transfers etc.
England has been a monarchy for a thousand years and still is. Parliament is a nice thingy but the queen can get rid of it if she wants and she knows that. That's why they behave themselves most of the time. In fact she did this in recent memory in Australia.
All governments fail, but some fail faster and more spectacularly than others.
(I don't have time to give you every thing said by the founders on the danger of democracy and it's nTueal tension with individual rights... Here's a good starting point https://finance.townhall.com/columnists/jimhuntzinger/2018/1...)