For anyone having trouble with the launcher, you can bypass it entirely. In your Steam library, right-click on Civilization VI and go to "Properties". Under Launch Options, put something like this (with the quotation marks):
"C:\Program Files (x86)\Steam\SteamApps\common\Sid Meier's Civilization VI\Base\Binaries\Win64Steam\CivilizationVI_DX12.exe" %command%
You'll have to figure out where your game is installed, though.
This worked for me. I had wondered why loads times and turns were taking so long after that patch. Thanks much