Nothing to do with that. He threw out the referendum promise in order to secure power, and then failed to get Europe to agree to the headline changes which would easily have secured the vote in his "renegotiation".
"Austerity" is not to blame for this. You can argue EU recalcitrance played a part, as did labour party weakness, but it's on him. His legacy will be this vote, this loss, and his failure to see through the consequences of his actions.
In Netherlands they changed the way unemployment is measured. Was something similar done in UK? The change it Netherlands makes me not trust easy figures anymore.
Further, seems in UK there's quite a big difference between working and actually having enough to live comfortably. A lot rely on support or barely can afford anything.
Anyway, that is my impression and don't mind being proved wrong.
We've not had austerity of the same severity as Spain or Greece but that's not to say we haven't had it. We have. Cameron (and Boris, Gove, etc) have no idea how it's affected poor people.
"Austerity" is not to blame for this. You can argue EU recalcitrance played a part, as did labour party weakness, but it's on him. His legacy will be this vote, this loss, and his failure to see through the consequences of his actions.