The original post made some extraordinary claims, and I'm not seeing anything to the degree they claimed. To be sure, Windows 10 shares more data with Microsoft than I'd be comfortable with, particularly if Cortana is enabled, but it doesn't seem to be anything like the levels described in the article. I wish the original poster had posted more about the type of traffic he was seeing, the specific requests, or even his methodology for testing.
The only dubious behavior I observed was sending every keystroke in the Windows Start Menu to the servers, but I understand that combined Computer/Web search is being sold as a feature, and this is necessary for that feature. I don't know why all the metadata is needed, and it's possibly excessive, but this isn't the keylogger the original post claimed.
Unfortunately, it's impossible to disprove his claims, but if it's as bad as suggested, reproducing it should've been possible, and I've been unable to reproduce it. I encourage others to try it as well -- if enough of us do it, it should be possible to either confirm or strongly refute the original claims.