I’m of a different opinion than most because I almost always take the bus, even though I always drive so have a car. I spend over 90 min a day commuting, and not having to drive is part of the joy of a vacation (especially as it’s a 7+ hour drive each way to WDW for me - and I get ZERO pleasure out of the act of driving). NOT having to hike out to my car at the resort, driving, waiting at the entrance to the parking lot, parking, and hiking in from the parking lot (or waiting for a tram) are probably 90% of the reason I always stay on site. And not having to worry about drinking and driving is another plus. In all of my trips, only once or twice have I had an unusually long wait to get a bus, and those were at park closing heading back to the hotel.
And in all honesty, if it takes me 5-10 - or even 20 - minutes longer to get to a park, it’s no big deal for me. I truly believe that all of the parking and walking at both ends of the drive pretty much evens out the actual room-to-gate travel time.
Driving can be a convenience if traveling between resorts, but even then you have to find parking and probably pay for it.
I can’t comment on the stroller factor as I have never gone to WDW with kids.