Is a stair floor plan 2x1/4 spiraled + landing possible with a maximum of 2.4x2.4m?

I think the stairwell is wasted space,

Your stair dimension indicates a spiral staircase, i.e. with a narrower stairwell only the unusable part of the steps would become wider and the centerline shifted there. That would not be any gain at all. A second time it would not be a gain either, since more width acts in proportion as shortening. With straight staircases I would otherwise agree with you, but here I think that the more generous stairwell is most likely to create a feeling of "spaciousness".

Good point, I hadn't considered that. That means the narrower eye could be beneficial only for transporting objects upwards, right?

That means, the narrower eye could only be somewhat beneficial for transporting objects upwards, right?

Also in this regard probably only marginally, precisely because the gain is near the coil.

depending on what kind of items need to be moved up, a large stairwell opening is sometimes practical. if the item is for example rather narrow but long, you can easily "pull it up" through the stairwell opening. but how often does that really happen

Thank you for the notes, I think we will leave the floor plan as it is then.