I tried to keep the example simple since this is ELI5. If you take the number of electors a state has a divide it by the states population, you'll get its electors per capita.

28 electors for 19 million people equals 1.47 electors per million people for New York.

30 electors for 22 million people equals 1.36 electors per million people for Florida

Idaho gets 4 electors for 2 million people equals 2 electors per million.

Since it's the number of electors sent to Washington that decide who gets to be president, sending more electors per capita means a state has more influence on the outcome.

50% of Americans live in just 9 states. The other 50% live in the remaining 41 states. If the 9 states all voted one way, and the 41 other states voted the other, the popular vote would be 50/50, but the electoral college results would be a landslide victory for whoever won in 41 states.

The main reason someone becomes president while losing the popular vote is because they won the electors from a bunch of the smaller states. Smaller states are less populated and more rural. Rural people tend to vote conservative since they benefit less from progressive policies and prefer tradition. Conservatives therefore have an edge due to the electoral college. There were 4 presidents that won without the popular vote. All of them were Republican. Given there have only been 59 elections in American history, that's a 6.8% chance the loser of the popular vote wins.