I believe that there is still a ton of laziness out there among USA voters. An unwillingness to actually look into things.
FTFY
I honestly believe that the NationalPopularVote.com plan would hugely increase electorate engagement and information. Make everybody's vote for president count equally. No need to bother with a constitutional amendment to get it done.
But most voters live in a place like me. The most highly covered political race has already been determined. There's no reason for me to go to the trouble of voting for POTUS, my legislature is definitely going to send all the Indiana delegates to appoint Trump next Wednesday. Since I can't effectively vote for president, why not just take a long lunch on Tuesday?
Tom