Oh dear, where to even start....
Our country is not known for "generous" packages of anything for rural areas. That's why we have such a problem now, and there's no sign that attitude will change any time soon.
In essence, relocation without any assistance is already in progress. Young people continue to migrate to the urban areas, leaving the rural areas with fewer and fewer people and an aging population. The young people who are left behind have either low education/skills, agricultural skills which don't qualify for anything beyond a Walmart greeter, are mired in addiction, or are taking care of family. The old people are quite literally crippled -- there's nothing like a lifetime of hard manual labor to bang up your body. (Incidentally, this is one the reasons opioid addiction is so high in rural areas, there are a lot of people in pain.)
Moving some 4 to 5 million people into urban areas -- away from the tenuous support systems of their family, church and neighbors -- is not going to improve anyone's situation. We'll just be swelling the ranks of the homeless and destitute because we already are facing severe housing shortages in just about every major city in the country. The housing shortage contributes to the reliance on cars and gas, because increasingly people have to commute long distances to reach their job, because it's not possible to live close to them. And we don't have reliable, comprehensive public transportation. In the not too distant future, we'll face even more migration pressure as people are forced to leave the coasts. And live where?
It's easy to say: We must do these things anyway. And eventually we probably will, when things are so bad that we have no other choice.