You can have a comfortable temperature 21C/72F, but a too-high RH, and since the temperature is correct, the AC won't kick in. Having an hygrometer helps with this.
Whole-house dehumidifiers are more popular in humid climate zones, which also tend to be hot/not-cold. Though there are places that are both, at times cold and hot/humid:
However, the general point stands in mostly-cold zones: it is possible to control humidity independently of temperature.
Also, most people want good indoor air quality, so bringing in filtered outside air, and tempering it with exhausted stale air is becoming more common (and is part of the building code in many regions):
* https://www.santa-fe-products.com/product-category/dehumidif...
You can have a comfortable temperature 21C/72F, but a too-high RH, and since the temperature is correct, the AC won't kick in. Having an hygrometer helps with this.