If you read their link "detailed data"[0] you can see there is an issue but you can also see that the level of invasion is low with most telemetry disabled.
This article links to that, but then ignores that author's conclusions (that it is a relatively light level of privacy invasion) to draw this conclusion:
> So how concerned should users be about Windows 10’s default data collection policies? I would say very.
But the author's articles are only really pro-Apple and anti-Microsoft, just look at their back catalogue [1]. They've written about Windows 10 problems weekly for months, getting more and more inflammatory each time.
So how concerned should readers be about the author's obvious bias? I would say very.
[0] http://arstechnica.co.uk/information-technology/2015/08/even...