I don’t think it’s clear that the popular vote would have been the same had people thought their vote always counted. If you’re in CA or NY, you know the outcome–your state will go democrat. So why bother vote unless you have an opinion on local issues?
Hillary won by 400K popular vote which is a super-small percentage of the vote (0.3%). So the question is are there just 400K more people who would’ve shown up for Trump if they knew how close the election would’ve been. The decision to vote is very different when you know your state will go blue by a 3:4 margin than if you think the vote will be super close, and you as an individual could literally make the difference like in Florida.
It also makes a difference in how the candidates campaign. Did Trump even come to CA? Why bother? If candidates knew it was a popular vote, they’d hit the big cities much harder and not bother with the burbs. Instead the EV makes it the opposite.
The rules of the game are clear, and everyone plays the game accordingly whether they realize it or not. So it’s not meaningful to calculate the score differently and then say “Oh but, if we’d done it that way, someone else would’ve won.”