The 'fast cars rev high and it never does them any harm' is a specious argument. Race cars, rally cars etc. never look for engine longevity; The engines are rebuilt or replaced every couple of thousand miles. I've never seen an F1 engine fail because it's been driven long enough to suffer from worn crank journals or bearings. On the other hand, I can show you a thousand boy racers who 'buzz' their engines on startup and blow blue smoke at 20,000 miles.
'not letting it idle' is a different argument entirely. When it pertains to not 'warming the car up at idle' then I actually agree entirely. What you get is a fully-warmed engine and a stone-cold transmission. -It USED to be more applicable to cars like the original mini, which had an in-sump transmission which shared the engine oil for its gearbox... but for end-on transmissions (like all cars nowadays) it's not a good idea at all.
Also, with rally and race cars, they WARM the engine up with electrical heaters before they start up, thus the oil is thinned out significantly. in road cars which are being re-started after running into the shop for ten minutes, the oil will still be nice and thin. My Porsche has an anti-drainback
valve which helps keep the top end filled with oil, -I don't know if the VW or the Audi do, though I think there may be anti-drainback spring-and-ball-type valves in the oil filter...
Either way, oil DOES leak slowly back, and there is usually LESS than the optimal amount when the engine is started after a long rest.
When the engine is COLD, the oil's viscosity is thickest. This means that you should perhaps imagine two conditions; one tryong to pump warm water through a small hole or a thin straw (representing warm oil being pumped through the oiling paths and galleries in the engine) and secondly something like Lyle's Golden Syrup being pumped through the SAME thin holes and galleries. This is like COLD oil, which has a much higher viscosity than warm oil.
Imagining golden syrup or treacle, you can see that it will be "tight" to squeze through, and so the pressure rises, even though very little 'flow' is taking place. With only a little oil in the crank bearing clearances, and no new flow yet, the thin film of cold oil on the bearing surfaces tends to 'tear' or sheer if the surface speed diference is too great, unless new oil gets there FAST.
This means that it is best to not 'buzz' the engine on a cold startup until the oil has gotten around everywhere.
If you have an oil pressure gauge, you'll know that the idle pressure drops when the car is warm. However, this doesn't mean there's less oil being pumped... it's just that there's more oil FLOW relieving the pressure. At COLD idle, there's so little flow that you'd be an absolute FOOL to 'buzz' the motor unless the cost of frequent engine work is trivial to you...
...Like if you're a Ferrari owner, a race team owner, rally driver, etc.
Keith