Around 26% of toys bought at Christmas are neglected by the end of January, and 40% will be thrown out within the first 3 months of being unwrapped. Combined weight of electronic toys comes to 3.2b kg
I always say that if the child is over 10 years old, the best gift is cash money. They'll learn about savings/spending, and be able to get what they really want.
Sure, but gift giving is supposed to be about showing that you care and cash generally is a poor vehicle for that. Buying a plushie of their favorite YouTuber that they can't shut up about proves that you do listen even though you often say "that's great honey but can you please put on your shoes so we can get to school on time today?" while they're mid sentence.
The waste really comes from the gifts that target the age group (and gender and other demographic attributes) but not the individual. My son got an electric race track that he'll use max two times more before it will end up in storage and forgotten, because the uncle that gave it knows his age and that he's a boy and little outside of that because he's not engaged and part of his life. He just happened to visit on Christmas this year.
Your story makes my point perfectly. The Uncle was told that 'this is what boys like' and forgot his own past. I never met a kid who didn't like having cash in their pocket. It makes them feel like a grown up who can make their own choices.
A while back, I gave a friend of mine $50 in 'gold' US dollars. I put it in a drawstring purse [the kind Conan or Robin Hood carries] and he loved it.