This opinion piece is false and offers no real evidence.
When did American kids start to go Trick o'Treating? Let's put it this way
It's the Great Pumpkin, Charlie Brown came out in 1966 on CBS. If that was already on TV by then, then I am pretty certain that celebrating Halloween in the US was already going on before then.
The modern American celebration of Halloween owes nothing to gay men and women.
Gays are not the "arche" / origin of Halloween. Nor did we really even make a new and novel idea that is part of Halloween. To use a metaphor, there are dozens of musicians / artists who influenced the development of rock and roll, well Elvis Aaron Presley is probably one of the least important people on the style of sound of Rock and Roll music, but his contribution was just to make the music more popular in certain types of markets.
Well Halloween was a child holiday a long time ago, but the "Halloween parades" in certain gay neighborhoods of the 70s and 80s started to introduce the idea of Halloween as an adult holiday too. Aka the gays were a virus inside the system who help interject Halloween into the adult non gay population as a serious / silly holiday, even though the gays were just the vector and many of the ideas are reminiscent of the much older "Carnival culture" near lent.
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Learning about "origins" is beautiful and help our understanding of who we are in the present by learning about our history, but also beautiful is learning about "remixes" and how things change over time. There is no perfect / original, it is human ingenuity causing things to change over time and ascribe new meaning. We as humans do this to "tools" but we also do this to our "culture" and our "mythology."
All hail the remix, improvisation and jazz!
Aka this (which you can argue is revisionist history) but I think this movie scene does a great job demonstrating my point.