Well, the stockpile is likely going to suffer from those same bans, but yeah, I understand the sudden spikes in demand.
Which is why I think you’re overestimating how much a billion gold is. 6000 gold for flying (slightly less, but it’s an easy number to work with). 1 billion / 6 thousand = 166,667.
Only 166,667 characters have to buy the gold for their flying for that stockpile to be gone. Now add training, profession costs, enchants, reputation items, repairs, respecs. Take a look at how prominent GDKPs are, an inflated economy with tons of new BiS BoEs to sell, profession materials and cooldowns. Then consider human nature. People will just buy gold to have it even though they don’t need it.
They’re going to keep farming gold. We both agree on that. If they didn’t keep farming gold, that billion is gone really fast. It is, as you say, only a buffer for the sudden increased demand.
The argument as to whether they will use the boost or not is not tied to how much gold they have. I believe I’ve seen you make the argument they’d just spin up more accounts instead. In this case, the stockpile is not a valid argument that they will not use the boost, but that they will not take ANY steps to ramp up production, including making more accounts.
So the question becomes… will they ramp up production? At what point do they cap off and say “we’re making enough gold, now there’s no point in farming any harder.” You say they already reached that. Okay, so regardless of whether they’d spend their money on the boost or on more accounts, they’ll be doing neither.
Therefore… the stockpile is not consequential.
If anything, if the stockpile IS consequential, the sudden spike of demand serves as an argument FOR bots/gold sellers using the boost. Sudden demand, stockpile not large enough, need gold NOW. Can’t wait 3 days when people are buying epic flying RIGHT NOW. You think EVERY gold seller has a billion gold ready?