Despite the electrical risks, it's crazy how much Christmas safety has improved.
I remember https://i.imgur.com/vKbfzEs.jpg from my childhood. Small metal clips to attach real candles to the Christmas tree. 20-50 open flame candles on a dried out Spruce, one of the best fire starters possible.
Why? That looks like a guaranteed way to result in an accident for a pretty minor novelty. If nothing else, using leds that look like candles would be less maintenance with the huge upside that they are incredibly unlikely to be able to start a fire.
Some people in Central Europe still use real candles on the Christmas tree. Of course, you place the candles carefully and don't leave them unattended.
(I have no idea how common it is, but I've seen the candles and brackets for sale.)
If it was a guaranteed accident like you suggest people wouldn't have done it for decades. Not the safest thing, but judging by the news it seems not even close to all the injuries weeks later from fireworks.
It somehow never occurred to me that - obviously the traditional Christmas lights were candles. Unless the original method was to cut at tree, decorate a still wet one for a day, and then toss it - how did anyone ever consider that a good idea?
Could be worse: use last-year's spruce/fir preserved using glycerine and/or formaldehyde. Try eco-friendly or self-made decoration from real hay, paper, and wood instead of metal or plastic. Use combustible adhesive to bend into form. Also, use candles from bee's wax instead of parrafin or stearin for extra temperature, flame height, and CO. No risk, no fun ;)
