The reason the electoral college was not the cause of Hillary's loss of the election, is that she had the opportunity to campaign in all the states as well as Trump did. If she had set foot in WI, IL, ID, OH, etc., then she might have won.
But she did not.
She deliberately ran a campaign based on popular vote, knowing that the electoral college was in force.
So it was all her own fault, and can't blame anyone else.
If the electoral college had not existed, Trump would still have won, because then he would have also run a popular vote campaign as well, and also skipped the smaller states.