They were held up by the chorra whore in the Casa Rosada who refused to cosign on the loans needed to finance these projects, the political allies of said puta viejita who sued to keep the Subte prices ridiculously low which cost the city 10s of millions of dollars, and the unions aligned with the aforementioned Embezzler & Chief who slowed work to a crawl and/or refused to work so that lines weren't completed.
Hopefully investigations into the embezzling of billions of dollars by FvP will lead to recovering hundreds of millions of those stolen dollars, if not billions of dollars and work on the Subte can speed up.
Other than Mugabe in Zimbabwe & Chavez in Venezuela, I've never seen a President purposefully do more to hinder the development of and/or destroy their country out of spite than CFK.