Frequently, new patches enable all mods. That's probably why the Scout Cat was enabled.It wasn't included in a patch per se since you needed to link your 2K account to get it. But, it was available at the same time as GS when it launched in Feb. 2019. And, AFAIK it's never been enabled by default, so the only reason you'd need to manually disable it is if you had enabled it previously.
Steam :: Sid Meier's Civilization VI :: Link your 2K Account to Unlock the Scout Cat in Civilization VIFancy yourself a friend of the felines? Sign up for a 2K Account and link it to your copy of Civilization VI and you’ll unlock this free skin for the Scout that replaces his usual trusty canine companion with a clowder of cat explorers! New 2K Account Signing up for a 2K Account is easy! Simply...steamcommunity.com
p.s. I like it and have it enabled all the time.