I forgot where I read the article, but someone mentioned that the Softbank strategy seems to be to geared towards having 2 major players in ridesharing/delivery in each market. The idea was that when these companies go public, they will stop subsidizing rides as much in order to show profit, and will become viable businesses.

Because these companies have a new war chest of money, if any new upstarts come into the game, they can have a short-term price war to drive these players out. The US seems to be the first market where this strategy will play out.