Expand the bike lanes into what? I don’t have the Australian experience. The places where infrastructure is compact enough to benefit from bike lanes in the US have already been expanded to be, effectively, wall to wall car ways with sidewalks. It does become a sort of zero sum game from a surface area argument of car vs bike vs pedestrian vs building. So, from a tangible perspective, cars lose ground. It’s too much of a mental simulation to imagine how reducing car lanes becomes a benefit to those that must drive because of a reduction of traffic and potential improvement to overall flow.