By "the electoral college" most people seem to mean that each state has influence disproportionate to its population, because every state gets two electors regardless of size. Ignoring that that is independent of the electoral college, disproportionate power isn't where most of the problem arises. The problem is that most states do not allocate their electors proportionally to how their citizens voted. Almost all states give all electors to the majority winner in the state. It's not required to do it that way, and Maine and Nebraska allocate at least some of their electors based on the proportion of the vote.
If states allocated their electors solely based on the proportion of votes in the state, that would achieve what a national popular vote would achieve and more. For example, Trump won despite losing the poplar vote, but if states had instead allocated their electors proportionally to voters within the state, Trump would have lost.
Why do this instead of a national popular vote? First-past-the-post voting systems result in two party systems with a lot of conflict. Ranked choice systems elect representatives that are more agreeable to everyone. A national popular vote entrenches a bad system, making it harder to ever get a rank choice system.
More importantly from a pragmatic standpoint, it's much harder to get a national popular vote implemented. To work, almost all of the states would need to get on board, but there's no individual-level incentive for citizens of a state to agree to it. Why would the majority of citizens of Montana agree to send their electors to the national popular vote winner when it's likely not the person they voted for? How are you going to convince them to join? The majority of people there won't want that, so they won't pass the law.
If states allocate based on proportion, individuals won't be concerned that their votes will ever support a candidate they don't like. It also doesn't matter whether other states hop on board. Maine and Nebraska are proof of this. They changed their allocation schemes without regard for any other state. At the individual level, the choice is easy; no one wants their vote to go toward a candidate they don't like, and the current system AND the national popular vote system both do that. If you think about your own views, are you in a state that the majority of the time the majority of people vote for a candidate you don't like? Wouldn't you rather have your state allocate proportionally? Are you in a place where the majority of the time your state goes the way you do? Are you happy that your neighbors' opinions are suppressed? It's pretty easy to get on board at an individual level, so that makes it easy to pass within a state.
People should give up on national popular vote and focus on getting their state to switch to proportional allocation. If you really want progress, target some key states: Florida, Ohio, Texas, Michigan, Arizona, Georgia, California, New York, Pennsylvania, Illinois.