From the article:

The consumer champion Which? found companies appear to be gathering far more data than is needed for products to function. This includes smart TVs that ask for users’ viewing habits and a smart washing machine that requires people’s date of birth. Rocio Concha, director of policy and advocacy at Which?, said: “Consumers have already paid for smart products, in some cases thousands of pounds, so it is excessive that they have to continue to ‘pay’ with their personal information.”