Hey there, sorry Im late but I only found this now. Wooden shoes have been developed from a sort of wooden sandals, the oldest full clog I know of was found in Rotterdam in the 13th century. However, it is not only the dutch that used wooden clogs, in fact, they were popular all over europe (spain, france, germany, denmark,...). Their popularity can be attributed to the advantages they have: They are cheap and fairly easy to manufacture, they keep your feet dry, clean and safe, they insulate your feet and air ventilation and the loose fit guarantee healthy feet. It is interesting to note however, that nowadays, wooden clogs play little to no role in other countries than the Netherlands. Personally I have two theories why this is the case. I havent found sources on this, just my own observations.

Due to massive material shortages, wooden clog (klompen in dutch) production reached a peak in both world wars. E.g. in 1942, when the population was around 9 million, the klompen output was around 5.5 million. You can imagine how many people were wearing clogs back then. To this day, the importance of the clog as a peoples shoe is implemented in the collective memory.

The klomp had a revival as a tourist item. To gain popularity, it was presented as the traditional shoe of the country, similar to what happened to bavarian leather pants in the 1970s.

The fact that klompen are very uncomfortable at the heel if you walk up a hill may also play a role. If you look at the regions where wooden shoes were worn, you will realize they are all very flat.

I hope I was able to give a little insight.