I think what killed the streetcar lines was two factors:
1. It was MUCH easier to adjust bus lines to accommodate changes in ridership patterns.
2. Streetcars--unlike today's modern, articulated trolleys--had relatively low passenger load per streetcar. That's why in Hong Kong, they used double-decker trams to accommodate more passengers per tram.
Today's really modern streetcar systems tend to use larger capacity vehicles than the old PCC's. And they're generally low-floor vehicles to make them more friendly to disabled passengers.
1. It was MUCH easier to adjust bus lines to accommodate changes in ridership patterns.
2. Streetcars--unlike today's modern, articulated trolleys--had relatively low passenger load per streetcar. That's why in Hong Kong, they used double-decker trams to accommodate more passengers per tram.
Today's really modern streetcar systems tend to use larger capacity vehicles than the old PCC's. And they're generally low-floor vehicles to make them more friendly to disabled passengers.