I don't see that anything has changed, so please help me out here.
I tried to run ads with IDN display URLs and the Adwords system rejects them. I mailed adwords support for manual approval, and they refused - told me that Google classifies IDNs as "vanity URLs".
From the article you mentioned:
Adwords support basically told me that you can't use "köln.com" as a display URL because it doesn't match the real domain name, which is "xn--kln-sna.com". I was back and forth with them about this all of January, February, and also in March.
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