Disenfranchising people based on income is a blueprint for a slave state.
No more so than our current form of government. The populace is divided into democratic party clients and slaves of democratic party clients.
Allowing people on public assistance to vote for ever more public assistance makes slaves of everyone who isn't on it.
Over the last sixty years the entire economy has been transferred several times from workers to looters. It has created a tremendous incentive to move from the workers to the looters, it has destroyed families, massively increasing social problems and moving even more people to the looter side of the balance sheet.
And what turns people into slaves is not whether they can vote in any situation, but whether they can get into a situation to vote.