It's insignificant because gold is becoming insignificant. The fact that it alone is the only thing being removed from the economy is enough, the % doesn't matter. Not even something like unsocketing gems destroying the item or gem -- just gold. It's been less than a month, RMAH isn't even out and the value has plummeted.
Anything that would go for huge sums of gold will be valuable enough that it's going on the RMAH or being $old or traded in/outside the game. People did this in D2 when it was even less convenient than it's going to be here. Inventories full of stuff, duped or not, on forums & ebay for peanuts. I'll give you 100 SOJs. No one will want gold, that's the point. Take 90% of it; in a month or two no one will care. There will be too much "stuff" that's worth more than gold.
Every game? Eh, we're talking Diablo. We don't need other games when we (some of us) have all the economic history of Diablo II etched into our brains. You could argue that was a different game and I might agree if they didn't start off in exactly the same manner (bots, exploits, dupes, currency value rapidly deteriorating, Blizz being reactive instead of proactive with slow response time).
Also, those bumps in the road never went away over a decade. Slap a ladder on 'er.