Yes. Bikes stick to the right hand side. The point of my photo is that counter-flow bike traffic isn't inherently dangerous: in some contexts it's not only tolerated but (as the markings show) legal. When they first marked my street like that, I refrained from riding counter-flow for a couple of years; but eventually I tried it and realized that in this special case (narrow one lane one way streets) it eliminates right hooks and gives the rider a clear view of traffic. (In my location, we're surrounded by so many one-way streets that if a driver passes our apartment, getting back to our front door takes a kilometer and involves 6 traffic signals, 2 left turns, 1 right turn, and a U-turn at a busy intersection). In addition, since COVID, when people got freaked about using the buses and metro, bike use has skyrocketed and the speed limit for cars has decreased (from 50 km/h to 30). AFAIK, there have been very very few bike fatalities related to counter-flow riding (there was a notable case last fall of a car that was driving illegally in a bike lane right near La Madeleine who clipped a rider from behind, then in the ensuing argument the driver drove over the rider, killing him -- but they were both going in the same direction).

I wouldn't ride counter-flow where drivers don't expect to see it (like, in the countryside outside of Paris). My post is to say that riding against the flow is, like all things traffic-related, about expectations and protocols (sort of like protocols about the assignment of right-of-way, which is pretty arbitrary).