Interesting -- is this a case of British perceptions of/approaches to what is considered "safe" being different from American ones?
There is another example I've come across where a high chair approved for sale in the EU is specifically banned in the USA, so much so that the manufacturer won't even ship the item from the EU website to a US address:
https://www.stokke.com/GBR/en-gb/accessories/1871.html
I don't suppose that European babies are that much more at risk of injury from this high chair than American ones, despite the fact that they're allowed to use this product and it's considered safe for them -- so I wonder about car/plane seats too...