After spending a fair amount of the weekend playing the open dev of Humankind:
1. The devs do have a lot to be proud of in Civ VI. There are a few things that I really am jazzed about with Humankind, but the Civ series has taken a strong leap forward in Civ VI and Humankind is more like Civ 6.5 as a result.
2. As much as I would love to see some significant improvements in the current Civ VI iteration (more challenging AI, better more robust diplomacy, bug fixes, etc.), I would completely understand the Firaxis team cashing in their chips here, and focusing more significantly on Civ VII. I think this is the right business decision -- and not try to go head to head with Humankind launch with a 5+ year old engine that is frightfully flawed.
3. What could actually -help- sales in the Humankind shadow is release of DLL. It wouldn't surprise me if it gets released in the coming months as a result.
4. I would predict one last patch, likely a few months out, to fix some of the glaring bug issues....and that is it.
I don't think the Firaxis team need to worry too much about Humankind from the vantage point of people purchasing one game or the other.....I think that Humankind is coming at that lull in the dev cycle where Firaxis can pay attention to how it is received, etc. without the direct pressure of head to head competition.
For what it's worth, I'm looking forward to Humankind's full release -- will be good to have some fresh ideas come into the series.