She caused the depression by closing down manual labor jobs and by effectively disabling the trade unions, all whilst campaigning for the poor to pay more tax and the rich to pay less. She was the main cause for the economic instability her great-great-great grandchildren will still be dealing with.
Thatcher was the conduit of neoliberal capitalism into the UK. Her Conservative government policies of privatisation, hobbling the trade unions, cuts to education and social services directly lead to the increase of wealth for the elite and the increase of austerity for the rest. Her actions and her neoliberal agenda continue to this day, and have become the mainstream (she counted New Labour as one of her greatest achievements). Her legacy is a colder, more individualistic, unequal world.