I think you don't exactly fully understand what IDNs exactly are. The situation with Google has nothing to do with IDNs, which are just normal domains in general.
Hell, if you want to target China, the first thought is to go with .CN. With IDNs, you can go with .com/.net (Chinese.COM/NET) and not have to worry about getting your domain taken away by CNNIC, which, IMO, actually STRENGTHENS Chinese IDNs. Throwing the word "IDNs" around in this context makes absolutely no sense when bashing it as a whole.