If you had actually read the article, instead of stepping in to blindly defend the corporation that is actively causing you to pay more money for games, you'd know this was not about steam key seller sites.
Uplay featured a $15 USD Rainbow Six Siege Starter Pack, but this version was not available on Steam, making the cheapest option on Valve's platform much more expensive. It's claimed Valve insisted Ubisoft swiftly remedy the discrepancy, giving the publisher "until the end of day tomorrow" to change that.