Actually temperature is relevant.

Extruding at low temperatures causes the filament to curl upwards at the point of extrusion, making it stick to the extruder and clump.
Extrude at a hotter temperature and the filament will hang straight down and not clump. Also extruding too fast has a similiar effect, but if you maintain the speed and up the temperature it fixes the issue.

As long as you're using a non-warping filament and a sticky bed, you can get away with a pretty large gap between the plate and the print head and the filament will stll lay down flat.
Something you learn when you don't calibrate the bed for a few months :-)

Yes if the filament doesn't stick to the bed - it will also clump.
And the not sticking might or might not be becasue the bed is badly levelled. Could simply be that the filament doesn't stick to the build surface.
And if that's the case - doesn't matter how tight you calibrate.

Not just one answer to any question round here :-)