The main argument I see for Halloween not being allowed is the history of Halloween, but nowadays the day is celebrated just to give candy, not as a satanic ritual. Does that change anything? Do we have to consider the history?

Islamic Law prohibits Muslims from supporting false beliefs and pagan beliefs. If celebrating Halloween in your society is perceived as supporting false ideas then it’s haram to celebrate it. However, if it’s not seen as such, and it’s just considered having a good time without supporting any false beliefs in any way, it would be permissible