These needs make heavy rail very high cost. PRT's low cost allows service to be diffused more widely. With more places to access PRT, big crowds don't have to collect, except at a few places where large events take place. Also, crowds don't have to build up, because, in the manner of using an escalator, travelers are constantly boarding PRT's small vehicles and leaving- at once rather than waiting in crowds to board or leave trains at one time. This dynamic would change the whole basis of determining demand and reckoning capacity to meet it.
Venture capital needs to hear that message.
If it did, that would help quicken further investment in such concepts and make them a practical reality before 2010.