General Contractor Construction Service Description

Controlled residential ventilation is not about mold but about ventilation. You get mold if you have cold spots where water can condense

No, then controlled residential ventilation would really be pointless. Ventilating like in the past to get rid of CO2 can be managed. There is always enough oxygen. However, the mold rate in houses is steadily increasing, especially in new well-insulated houses. But there are no more cold spots there...

How long have you been living in the house? How much do you ventilate and what is the average humidity?

I have been living for many years in apartments and houses without controlled residential ventilation, and I do not know any mold in apartments, our hygrometer shows around 40, in this house now for one year, in the previous one for 22 years

As long as the moisture does not condense on or just before a surface, there is no mold. The number of ventilations required to adjust the CO2 level considered appropriate can be found online at any time; a normally working person is usually unable to manage this. In houses without controlled residential ventilation, the window is often left tilted open, and moisture usually condenses there, leading to mold.

Condensation is a function of temperature and relative humidity. In some buildings, and I speak from experience, you won't reduce humidity unless you make ventilation your main job. With sufficient humidity, a few degrees of temperature difference are enough to cause condensation. If you look closely enough, you will find mold in every house. In modern houses, there tends to be more. With the CO2 content, according to recommended values, you are not entirely wrong, but personally, I have never had problems with it. But sure, you gladly take the bonus.