Just move bicycles from being grouped with cars to being grouped with walking, and you're correct.
Dutch cities are designed for walking and bicycles. It helps that the bicycles are also designed for dutch cities. Upright, comfortable, a bit heavy and slow, and can be locked up for short times without needing to be locked to anything.
You can't design a city for both walking and bicycles. You can only make compromises between them. The slow Dutch bicycles are still 2.5x to 3x faster than the average pedestrian, which makes them convenient for distances most people would not consider walkable. If most people are comfortable with using bicycles over such distances, it encourages a more spread out urban structure.
People often use bicycles in cities because they are convenient and as fast as or faster than driving a car or using public transport. That is the reason why bicycles should be grouped with other vehicles and not with walking.
>You can't design a city for both walking and bicycles.
Your assertion shows that you have never visited a Dutch city.
Most Dutch cities were originally designed for walking (they are old, at least in the core), then (like most places) the car took over in the 30s - 70s, but since the 70s there's been a concerted effort to re-establish bicycle supremacy, along with strong public transport.
The outcome is that pretty much everyone (including the elderly) cycle everywhere because it's most convenient. And walk around perfectly fine once you've parked your bike. And if you need to go a bit further afield when you're done? Jump back on the bike.
The hybrid of public transport/bike/walking works incredibly well, everyone co-exists perfectly, without making any compromises. Obviously, this wouldn't happen without there having had been a concerted effort to build good multi-modal infrastructure nationwide for the last ~50 years, but it really pays off. The urban environment is really nothing like pretty much anywhere else.
It'd be more apt to group them on their own if anything, just as Dutch cities tend to have separate lanes for cyclists, drivers and pedestrians. At least for The Netherlands, cyclists often feel like a protected group both pedestrians and drivers have to pay attention to.
The latter is more apparent in old roads and areas where there's no clear distinction between road and sidewalk, where cars are generally not allowed but bicycles are. Watching for cyclists feels like playing Frogger at times. Also cases where cyclists just ignore pedestrians and expect priority, when it is obvious pedestrians have priority (zebra crossings, traffic lights).
The above does illustrate why cities made for walking alone and cities made for walking and cycling would or should differ.
It is becoming very clear from your comments you have not seen the thing you're criticizing, bur rather argue from a paradigm you're familiar with. So I am going to join the chorus here and advise you to visit a dutch city, so you can yourself experience that there's more than one design paradigm that is valid, when it comes to urban planning.
> You can't design a city for both walking and bicycles.
It seems more appropriate to me to say: You can't optimise a city for both walking and bicycles. You can certainly design it for both (and even public transport and cars), with the necessary trade-offs.
Dutch cities are designed for walking and bicycles. It helps that the bicycles are also designed for dutch cities. Upright, comfortable, a bit heavy and slow, and can be locked up for short times without needing to be locked to anything.