The Electoral College exists for the same reason we have a bicameral Congress: to level the playing field and keep the bigger states from having all the power and to give the smaller states a greater voice in the lawmaking process.
When the Constitution was being formed, the bigger (more populous) states wanted representation based on population but the smaller states (less populous) wanted representation limited to an equal number of representatives regardless of population. So a compromise was formed and a two-part Congress was formed. A Senate where each state would have two and only two representatives (senators) and a House of Representatives which would have representatives proportional to state population. Both sides would have to approve a bill before it would sent to the President to be signed or vetoed. This spread the power around and kept it from being concentrated in any one group.
The Electoral College works much the same way. If you didn’t know this, each state is allocated a number of electoral votes equal to the number of congresspersons that state has in the House of Representatives plus two more for each of its senators. Basically, each state carries the same weight in the EC as it does in Congress.
New York, California, Illinois, Florida, and Texas are the five most populous states in the country. Taken together, these five have states have a greater population that all the other 45 states combined. If the president was chosen by a direct popular vote, then in theory these five states alone could decide a presidential election every time. The other states would never get any say-so.
The Founding Fathers knew what they were doing. And in the entire history of the United States, there have only been five times when a presidential candidate won the popular vote but lost the electoral vote. This was in 1824, 1876, 1888, 2000, and 2016. There is no need to change the system.
Footnote: After the third presidential debate, the Democrats got their feathers all ruffled when Donald Trump said he might not accept the results if he lost the election. Now who has their feathers ruffled?