Hello questioner.
There is hardly anything more to add than what "Zubi123" has already written.
The parquet elements, as far as I believe I can deduce from the photos, can be classified as multi-layer parquet (previously known as prefinished parquet).
The gaps are minimal considering the season!
We can only talk about "noticeably wide" gaps in nailed parquet planks in winter if gap widths of 5 to 10mm occasionally occur.
(In glued parquet, the gaps are naturally much smaller due to the rear restraint of length changes. But gaps are not a problem there after drying out; see the following note).
Now it is so that the gap width described by you of up to 0.5mm in glued multi-layer parquet planks is not always avoidable. However, the room humidity of rel. 37% is very low for wood and wood-based materials (including, among others, chipboard or OSB boards). And indeed harmful if this room climate prevails in the room for a longer period.
The person responsible for this, however, is the user, in this case, for a rental property, the tenant!!
If multi-layer parquet suffers delaminations between the carrier layer and the top layer due to permanent drying out (the probability is quite given), it would be interpreted negatively against the responsible party according to expert opinion. And that person ultimately bears the damage.
"Zubi123" also mentioned setting up a room humidifier.
The absolutely correct decision for both humans and parquet, even if you don't have a parquet floor.
For decades now, there have been questionable views in circulation that you could operate a decorative fountain in the living space and/or hang clay pipes with water on heating fins.
Purely mathematically, a significant effect caused by this is refutable. Unless, in an average room size of 40m², somewhere between 3 to 6 liters of water would have to be refilled because the clay pipes or the fountain would run dry.
This simple and understandable indication of the necessary (daily to be refilled) water volume should be convincing!
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The room humidifier must be adjusted to the corresponding room size (better: the room volume).
VENTURA washers have an excellent efficiency and are available for less money. I bought one of these back then in one of the large electronics stores – and was very satisfied for many years. You already notice the convincing sense of well-being difference between 35% and 60% rel. humidity upon entering the room.
Best regards and a wise decision wishes: KlaRa