Bridges have a very different quality standard than web browsers do. Chrome doesn't kill you and everyone around you when it crashes.
A better analogy would be bridge designers coming up with a design that required half as much maintenance or half as much material cost to achieve the same factor of safety, or which doubled the expected lifetime of the bridge for the same lifetime cost. Those would be significant improvements in the design, even though eventually the bridge will still have to be replaced (either all at once or piecemeal over its life).
A better analogy would be bridge designers coming up with a design that required half as much maintenance or half as much material cost to achieve the same factor of safety, or which doubled the expected lifetime of the bridge for the same lifetime cost. Those would be significant improvements in the design, even though eventually the bridge will still have to be replaced (either all at once or piecemeal over its life).