I’ve argued before that Americans perceive mass transit options as having different statuses. For those with more resources, trains and subways are preferable. If those are not easily accessible or the person has reached a certain status in life, driving is a must.
At the same time, bus service is relatively cheap for cities and communities to provide. Because American cities are often planned around cars and have spent decades trying to efficiently move vehicles around, adding or subtracting buses to adjust service levels is doable. In contrast, constructing new trains or subways can be incredibly costly and require years of work. It may be that in the long run trains and subways are better options to plan around but that requires a long-term commitment.