It's not a zero sum game.

Improving bicycling also improves public transit and walkability usually because bicycles take up so much less room than cars so buses have more space, and it's extremely rare for a bicycle to injure a pedestrian, but it happens hundreds of times a day just in the US alone with cars.

Also bicycle infrastructure is way cheaper to build and maintain than car infrastructure. And even when bicycle infrastructure is totally busted for awhile, people find a way around, where as with cars if there is any blockage it becomes an incredibly high priority emergency.