The question is more why do the shit politicians rise to the top. Outside forces (rich people and companies) have too much power and can exert too much influence.
In this case I’m particularly curious about the Danes. They insisted on this more than any other previous attempt. They are forever soiled as fighting against the will of the people.
It's been sold as "for the children". A very substantial proportion of the population are natural authoritarians, and this is red meat for them. Never mind that "the children" that they profess to be protecting are going to grow up living in an increasingly authoritarian surveillance state, this is what authoritarians want for our future, and they see it as not only morally good, but any opposition to it as indefensible.
Dumb and greedy voters, traditional and social media, and electoral interference are known reasons. But it's also a matter of compromise: you vote for a party because you agree with a bunch of their points, but almost certainly not all. Topics like privacy are ignored by the general public, so politicians are hardly held accountable for them.