I wouldn't say it didn't last. All Saints Day is still observed by 1.3 billion Catholics around the world. The modern day version of Hallowe'en is more an English-American phenomena, popularized in modern times by those who profit monetarily by it (candy, costumes, decorations, alcohol, etc.). Back when I was a kid in the 1960's it was fairly innocent, but now, as someone here mentioned, it has been turned into an excuse for adults to get drunk and celebrate gore and evil. Most other countries in the world don't celebrate it, and that is why El Salvador is wisely trying to get rid of it. It never was part of their own culture.
Who can blame these other countries, when they only see us exporting the worst of what the holiday has to offer?
But that’s out fault. It’s been our vigil and our holiday for over a thousand years, and we are now taking it back.
https://hoquessing.com/store/all-hallows-eve-prayers-and-devotions/