plugin suggests using fid when geometry is PointZM

[gdt]

With qgis 3.34.10 and up-to-date Contour plugin, I asked for contours from gpkg layer that has a "3D Measured Point" geometry column and a fid, and nothing else. (These are observations from an RTK GNSS receiver, and M is reported error.)

The plugin suggested fid for height, and it would be great if it instead ignored fid (as never height) and guessed that the Z from point was height.

[gdt]

Makes sense about geometry Z not being so common. Wow, 11 years ago and qgis 2! These days, I would expect most non-professional use to be RTK GNSS, as without RTK, elevations are low quality. I would expect professional use to be either RTK GNSS (seems good enough for topo), or robotic total station as part of surveying for wetlands/planning-permission site plan -- but I don't know what's typical for data formats coming out of professional data collectors.

FWIW, I gathered 160 data points over roughly 20m x 20m with an F9P, decent antenna, and a pole, not really leveling, over about 30m, and the generated contours at 20 cm look reasonable, rather than looking like contouting noise. I expected 1m or maybe 0.5m contours to look decent. (Yes, I know 20 cm is a very unusually fine grained as a contour interval!)