Land-based turbines can and do have an annual average net capacity factor of well over 40% of their nameplate MW depending on the local wind resource. Offshore turbines tend to produce even more as the air density is at a maximum at sea level, the winds tend to be steadier (depending on location) , and there is no interference (trees, hills, etc.).
The study I was referring to had at least 10,000 land based turbines in it, covering IIRC a five year time. Their performance was just under 30% for those turbines over that time frame. That included all downtime due to lack of wind, maintance, or any other reason they weren’t producing electricy.
40% is a huge jump from 30%, do you have a study to refer to?