It'd be interesting to see the corresponding public transit numbers. In the US, I'm not optimistic about a bike revolution lasting past covid. We've seen some new bike infra being deployed in Boston but not much more than we'd be getting anyway.

When you say car traffic, I presume congestion and not volume of cars. I'm sure volume is down overall and I recall from discussions about congestion pricing, even a 10% decrease in volume can result in congestion completely dissipating. In normal times, Induced Demand would lead to volume going back up as transit users convert back to cars.