I had a couple of friends try a number of online dating sites/apps over the past few years and whenever they would show me profiles I was pretty surprised to see so many women with a hard cutoff of not dating anyone under six foot. I never really realized how short I am at 5'9" prior to this.
Also largely (heh) an American thing. In Europe I've rarely if ever seen 'must be at least 180cm tall' (I know 6ft is 182, but 180 is similarly rounded). Could be we care less due to Old World tallness.. we are decently tall compared to Americans. See Scandinavia, West Europe, Balkans, etc.