What you are talking about is just simply political polarization which is done on purpose by poiticians, which happened whether DHH or Ashahi Linux devs wanted or not. Also there is real human element in both, I'm just going to an Omarchy meetup that's organized next week, and DHH is also organizing some (just not in my city).

I believe eventhough they won't work together directly, with open source they can just use eachothers code (I believe Omarchy is using Ashahi's M1-M3 code, but now people are already creating Omarchy M4 GPU support using AI, and Ashahi devs can look at how it's working and understand it, they just want to take things a bit slower to have less slop).