Not necessarily. Stimulated by this thread I started to explore the topic a little more (see also here). The picture below was developed “classic” IR. Custom white balance (spot on the field) and swapped channels (R<>B). To get more blue into the sky I increased the saturation of the blue with color zones. Unfortunately this also makes the white buildings bluish. At the end I adjusted the colors a bit with the tone curve.
This may not be the nicest result possible, but it comes closer to the picture on the site linked above compared even with the 590 nm filter.
With the help of masks you can certainly get more out of it, but I intentionally did this version without drawn masks.
DSCF3203.RAF.xmp (4.7 KB)