This seems to be correct. It's the same problem Civ VI saw, only ever seeing week-to-week growth in the first year if there was an update or sale. New Civ games aren't as engaging to most Civ players until years later.
We're close to having back to back weeks above 50%, for the first time since the opening 2 weeks. This week is on course to having the 3rd best week - so far 91 positive, 87 negative, 178 total, 51.1% positive.
I'm confused by "the week of October 20". Wouldn't that usually mean the week of October 20th - October 26th? It has only been one day, a Monday, so it's odd you'd choose this week of one day to use to compare, if that's what you mean. A better comparison is a Sunday to Sunday. Sunday 5th saw a peak of 12,617. 2 weeks later, Sunday 19th saw a peak of 10,404. That's a decrease of 17.5%. That's consistent with the 2 week drops from the previous updates, however it's the highest number out of the past 5 updates.
- 1.2.5: 12,617 to 10,404, 17.5% decrease
- 1.2.4: 11,871 to 9,670, 18.5% decrease
- 1.2.3: 11,758 to 9,595, 18.4% decrease
- 1.2.2: 11,911 to 10,066, 15.5% decrease
- 1.2.1: 11,707 to 9,652, 17.6% decrease