Your proposal falls prey to a sort of "investment-productivity monster." What if we identified the brightest kids in 2nd grade and spent all of our education resources on them, while shuffling the rest into the Amazon Fulfillment Centers? Maybe that'd increase overall productivity. But it'd be wrong.
Let's for a moment disregard that there are a lot more wheelchair users than young black women in Chicago, and that the wheelchair users obviously are a lot more disadvantaged - a government is not a business. Its goal is not necessarily to use money "ideally beneficial" in a utilitarian way - its goal is to keep a society working, which in our liberal democracy environment means protecting the weak and keeping things relatively fair (in the sense: to help those who cannot help themselves).
While every young black woman from Chicago can stay in school, attend night school, or spend time in a library, not even the most athletic wheelchair-user can consistently hop their wheelchair (plus body-weight) up the stairs. And even if every single black young Chicago-woman becomes a new entrepreneur, resulting in a larger net-good for society as a whole, the wheelchair-user still would have the same problem.