While I enjoy going for a walk (and will gladly walk four miles as a leisure activity), I don't enjoy wanting to go somewhere and needing to budget an extra hour (or more) for the extra two miles of walking each way, possibly in bad weather. It's like saying the buses always running a half hour late is a feature because it gives you some time to read.
I don't see how it's a "feature" if it only makes it pleasant if you're fully able-bodied, the weather is nice, there's no traffic, etc. People want to be able to get places. Having to add an hour to every trip because transit isn't near you is not a benefit.
Walking to the station isn't even the bad part. The bad part is then walking 3min in tunnels smelling like piss to get to the platform, then waiting 7min more for the train to arrive, then walk 3min more to get out of another piss-filled station. That's 10-15 of absolutely-not-enjoyable subway station.