Statehood Would Entrench Mismanagement
People tend to become complacent when they get what they want. People don't change habits much when they get married or a long-term relationship because someone thought they were good enough.
Children tend to study more if ice cream is a reward rather than study because they already got ice cream.
Giving more power to the political elite is just rewarding them for the mismanagement they have engaged in.
DC's unofficial motto is "Taxation without representation".
The political elite chose it as a way to point out the disconnect between one of the injustices that caused the American Revolution and DC's current lack of effective representation in Congress.
And yet, that same political elite has used the lack of statehood as an excuse for all sorts of mismanagement.
The Federal Marshalls removed 400 prisoners from the DC Jail because conditions were inhumane. If DC got statehood, the practices wouldn't get the the additional inspections. Congressional oversight is why DC had the emergency funds to continue to pay people during the COVID-10 lockdowns. DC's Housing Authority has been handled millions and has delivered very little.
For now, appeals to Congressional oversight and Federal agencies seems like the only real recourse for badly neglected voters. DC statehood would take away one of the few appeals left to ordinary people abandoned by poor leadership.
DC is not ready to be a state until there is some basic accountability for bad management.