To reitterate the wording from the owner manual for the VF, page 233, I'm sure VE is the same..
Always fill the tank at the intermediate or fast fill rate. Do not add any more fuel after the fuel filler first clicks off or fuel blow back. This allows room for the fuel to expand inside the tank.
Only trickle-fill tanks when the vehicle is to be driven for more than 50kms after the tank is filled. However this is not recommended on days above 30C.
Modern fuel systems are seal system built with the aim of reducing air pollution. As fuel expands due to heat, the tank must not be filled beyond a specific amount, so as to be able to accommodate fuel expansion. The bowser fuel hose trigger auto cut would be calibrated to ensure that fuel flow would stop once a specific back pressure is reached, which the vehicle's fuel tank designers would ensure actually occurs before the space reserved for fuel expansion is breached. I'm sure lots of thought goes into this system.
As fuel vapour can't be released into the atmosphere directly, there is a charcoal canister that is connected to the fuel tank and is used to absorb such vapours before the fuel free vapour exits the sealed system. During engine operation, the engine electronics opens a purge valve so outside fresh air can be drawn into the canister and further into the engine, thus removing the absorbed fuel vapour from the charcoal. The electronics is smart enough to measure tank pressure and other such parameters related to the sealed fuel system's correct operation and light up a check engine lamp is something doesn't work as it is supposed to. The check engine light is often called the money light for a reason
Overfilling the tank can result in reducing or fully removing the space that is "reserved" for fuel expansion. The problem then becomes one, where fuel expansion due to heat, will force fuel to be ejected into the line that goes to the charcoal canister filling it up with liquid and potentially even eject it out the canisters air line if pressure is high enough... This can occur even if the canister is above the tank filler neck as the flow is driven by the pressure of the expanding fuel, not by gravity
The real question is what damage can result from having fuel in the charcoal canister. I have no idea what the real answer is but I've read that the fuel can degrade the charcoal (sack?) and send granules through the system blocking solenoids and such. But being modern cars being a PITA to diagnose, in part because of their complexity and in part because mechanics either don't know, don't have time, can make more money doing oil changes, etc... the problem becomes one where you may have a check engine lamp shining its light, one that will cost to have investigated while hoping the "guy" isn't a "parts cannon" guy
Why don't we see lots of problems with fuel tank evap systems? May be it's because many drivers don't try and squeeze every drop into the tank, may be it's because many who do drive around 20km after a fill which uses 2litres of their overfill, or may be it's because some who have actually had issues don't really care much about getting their car sorted and begrudgingly drive around with the money light on...
Who knows the answers but if the manufacture states not to overfill the tank, and pump triggers are calibrated devices, I'd tend to head their statements else higher repair costs may occur down the line. (and I'd rather have some compressible air sapce witin the tank to avoid the fireball eruptions if someone high speed rear ends me while I'm turning left
)
YMMV
