I mean sure, if you take a surface-level look at things that is true, but the Dutch government has spent a lot of time, money and effort into actually thinking about their urban design and how they tackle building their cities for the quality of life of its inhabitants, rather than the QoL of its inhabitant's cars. It helps, of course, that it's a flat country, but just being flat isn't enough, it takes deliberate planning and good choices being made at the governmental level.

What's the excuse with cities like Oulu in Finland, which isn't flat and is covered in snow more often than it is dry? Despite those 2 potentially huge issues, they still have incredible cycling infrastructure. Or Switzerland, where in my experience in at least Geneva and Bern the cycling infrastructure was also superb despite the mountainous terrain? No one's saying you need a cross-country bicycle highway, as long as the dense urban centers have good bike infrastructure it's more than enough.

Also I didn't even mention bikes in the comment you were replying to, I was talking about public transport like trains, trams and buses. Again, Switzerland despite being extremely mountainous has a world-class rail system that literally cuts through massive mountains.