That first quote doesn't really reflect the law as it is now, which is reasonably (as far as IFAB goes at least) specific on this:
the ball touches a player’s hand/arm which has made their body unnaturally bigger (this is a handball offence)
the ball touches a player’s hand/arm which is close to their body and has not made their body unnaturally bigger (not a handball offence)
Like I said, it's pretty much impossible to run without arm movement, so there is nothing unnatural about that.
De Bruyne's sorted it out, why all the confusion?
"De Bruyne accepted the decision but questioned the new regulations, joking that players may need to lose limbs in order to ensure they stay on the right side of the law."
https://www.google.com/amp/s/www.independent.co.uk/sport/football/premier-league/man-city-spurs-handball-rule-law-kevin-de-bruyne-change-premier-league-a9064391.html%3famp