Well, you do need to walk to/from your bus stop. Might be marginal, though.

That being said, I'm in Europe and I typically cycle at least 1h per day from/to work/shopping/etc.

And for the bus you might be standing instead of sitting, you might have to change lines, etc. This is hyper easy to test with a $5 pedometer.

I'm willing to bet $100 that if you buy the pedometer and compare both commutes, the bus commute will mean that you have at least 2x the number of steps when you commute by bus versus when you commute by car (for the actual commute).

It's nitpicking. You can make 500 steps vs 100, and make a headline-like claim that it's five times more. In real life difference is negligible. Your organism requires walking in significant doses, and for you to practice it, you have to live in a walkable space (it includes infrastracture, and safety). A city can be driven by public transport, and not be pedestrian-friendly. A city can be private-car driven, and not be pedestrian-friendly.

> Sitting in a bus is still sitting, offering no health benefits vs sitting in a car

Actually no.

With a car, you get into the car outside your house, and you typically aim to park the car as close to physically possible to your destination.

With public transport, you have to walk to the nearest stop near your house, and you have to walk to your destination from the destination stop.

In addition, with trains you will have the opportunity to walk up and down stairs.

You might also walk to run errands around the local area, for example, walking to/from grocery shopping with a few bags, instead of driving to the supermarket, dumping the bags in the back of the car and only walking/carrying the limited distance between your car and the kitchen.

You might also opt to walk a slightly longer route if for example it takes you through a local park.

Walking to/from bus stop surely doesn't sound impressive. You can practice a smallscale shopping with every sort of transport (it depends more on available shopping infrastracture, and economical reasons). And you surely can walk more by choice irrespective of transport (it depends on available pedestrian-friendly infrastructure). Choice is choice, and sitting is still sitting.