Good overall question (manual vs. automatic) but regardless of the 3.0d (not for North America) you have sample bias. ALL E53 with V-8 were automatic only, so that will automatically (no pun intended) shift the % of manual lower.

You could look at the 3.0i (sold worldwide) and look at the %
You could also look at the 3.0d (sold in most countries aside Canada & US) and look at the %.

__________________
2002 Euro X5 (E53) 3.0 diesel (M57)
5 speed manual with UUC short shifter.
Pre-xDrive NV125 transfer case (chain & gears).
Factory Xenon headlights, Spyder LED tail lights
Updated vortex crankcase breather.
Motorsport dead pedal, factory fire extinguisher, factory first aid kit, factory F&R mud flaps, factory PDC

Bilstein B6 shocks F&R
Redline oil has replaced "lifetime" fluids (F&R diff, manual transmission, transfer case and P/S).
Dimple magnetic drain plugs in all compartments.