I think it's impossible to compare as so many parents have different ways of doing it. We've always spent about £200 oer child at Christmas, but every year we include in this lots of things we'd buy anyway - pants, vests, socks, pjs, slippers, dressing gowns, an outfit or two etc etc. These are usually mixed in with their Father Christmas Sacks, along with food items, toys and replenishables (arts and crafts etc) So that massively bumps up the cost.
Also, it needs to be compared to how much you spent over the year. I had a friend who would always make a point that she never spent more than £100 per child at Christmas and only ever did the "something you need, something to read" thing. All well abs good, except every week when she'd pop into town she'd pick something new up for her son. Whether that was a £4 magazine, new book or a toy she'd seen reduced (this could be more - £10-15). Whereas, if I saw something I thought my dc would like, I'd buy it and put it away in a box to give at Christmas.
So whilst she was very virtuous in only spending £75 to £100 at Christmas, if you added in the other 50 weeks of a year at £5 each -that's £250 + the £75 at Christmas, she spent over the course of the year way more than me! And that was just on toys. That didn't include clothes or things the child needed over the year.
And finally it's easy to spend not much when children are little, as toys are relatively cheap. We'll easily spend £800 on my daughter this Christmas, but that does include a set of driving lessons and a phone upgrade. So really, things she would have got anyway, just we make anything expensive double up as a Christmas gift.