Not an expert on this topic, but density of development in floodplains must matter. If concrete residential areas are separated by large drainage areas (lakes, reservoirs, ...), flood impacts will be reduced. E.g., recent flooding in Bengaluru—concrete jungles flood more easily than real jungles.

Agree. But I am thinking of the 2000s & before when climate wasn't really a concern. I see a lot of articles solely blaming old development models for current flooding, and wondering how realistic (economically, socially and politically) is it to expect such stringent and forward thinking rules then