Yes, we can find the answer as to why they were originally implemented.

However, my interpretation of the original question was that of "why are they still in existence?".

I feel the original question was more in the line of "Why are US presidential election are not like elections in the many other democratic countries?" and is a huge trivialization of a complicated issue.

Because you won't convince 3/4 of states to change it. And it's not worth a new constitutional convention over that issue.

We actually only need to convince another 105 electoral votes worth of states: https://en.wikipedia.org/wiki/National_Popular_Vote_Intersta...

I would also hope (I would write 'expect', but I am a bit cynical about the quality of US education) this was taught in elementary school.

People are also inclined to forget things they don't like.

Forget or deny to know? For people living in the USA, forgetting that must be quite a challenge; every four years, there's half a year of real reality tv, extensively covered all over the news, to remind them of it.

If the answer is so obvious then just post it

It's not obvious by any means, that's why I pointed to the reference work on that topic. There are reasons the electoral college was implemented, whether they are still valid of not is a different question entirely.

Furthermore, it's not even clear what the question is. Why it's not elected by the US populous? Because it's the President of the United States being elected, not the President of the people of the United States. Why is it not a direct vote? In part, to make the system resilient to the tyranny of majority which was feared by Founding Fathers.

There is extensive literature on that topic by the designers of the system itself and one cannot summarize it in a HN comment. So if the the Americans the parent was referring to are indeed puzzled by that question there are answers to be found.