It seems that since probably before 4.3.0 and still in 4.4.1, there is a layer height bug that results in bad Z positions. I do not know if they are missing layers or what. I made a bug report for it. I had to wonder why my wall layer heights of 0.14 with infill layer heights of 0.21 and support layer heights of 0.21 was resulting in 0.28 differences in Z. This explains why my prints have been coming out brittle and my infill has been wispy strings.
This may have been a misunderstanding of how Cura works. It rounds infill up to the nearest wall layer height. That makes it unsuitable for when you print somewhat thick in the first place. 0.2mm wall layer heights means a 0.4mm nozzle would get no squish if you try 0.4mm infill layer heights. If you try to do 0.3mm infill layer heights, it will turn it into 0.4mm infill layer heights and just mess it all up. I believe Slic3r was capable of doing 0.3mm infill layer heights with a 0.2mm wall layer height with a 0.4mm nozzle. The means to do it is just sometimes doing wall or infill twice sometimes so I do not see why Cura could not do that.
Hopefully, Cura gets an upgrade to their algorithm. I suppose if they do not, I can try 0.2mm walls with 0.4mm infill and support with either extra extrusion width or extra extrusion flow so that I get that desired squish.
I added a feature request.