No, not for many years.
It was reported on this board that it was to make it less convenient for anyone not staying on property to park at DTD at no charge and get to the parks.
Busses go from DTD to and from the resorts.
Take a bus from Downtown Disney to any resort and make a connection to a theme park bus. Actually you would choose a resort that is more or less in line as opposed to out of the way.
In some cases you can walk one leg (no pun intended) for example walk from DTD to Saratoga Springs and take one bus from there to a park.
This one confuses a lot of people. It is slightly annoying that you can't leave a park and go right to DTD. Last year we took a bus to SSR, then walked through the resort (got lost) and eventually found the water taxi that took us over to DTD. Luckily the water taxi was at the dock so there was no wait.