There are a number of problems with this:
- If 30 to 40% of most Asian economies collapse, you don't think this would have a negative impact on them?
- You think Asian societies have the correct structure to continue said advancements? Their overly strict societies that prevent straying from the social norms leaves much to be desired.
- Most Asian advancements come as a result of copy-catting innovative western ideas. With the fall of the west, who will they copy cat cheap products for?
- They may not collapse in the way that western nations will collapse, but a failure to provide for the masses will almost certainly be viewed as a mandate from heaven for the removal of the current regimes. East Asian civil wars last on average 300-400 years. That's 300-400 years they aren't focusing on transhuman technologies that can end human conflict.
- Most Asian states will become totalitarian and militaristic (this includes Japan) which will inevitably stifle progress.
There's no way around it. The collapse of western civilization will almost certainly result in a global collapse. Asian will recover much faster than everyone else, but their rigid societies will almost certainly reduce in technical innovation.