Cross-platform became so dominant because the same small dev teams had to support users across multiple platforms. Practically they either had to build ONLY for the web or use some kind of web-tech-based framework like Electron.
Agentic coding changes that constraint at a very low level. Teams are no longer limited by whether they have someone who knows how to build for iOS, Android, macOS, etc., or whether they have the bandwidth to maintain multiple native codebases. The cost of supporting multiple platforms starts to fall dramatically.
And I think this is closely related to the thesis behind Omarchy also. Setting up and customizing Linux is historically a lot of friction. If you wanted a system that was personal i.e. NOT (Mac OR PC) you often had to be comfortable troubleshooting obscure issues and spending hours getting everything just right. Don't get me wrong: a lot of people enjoy that friction. But it sucks at so many levels.
Agents lower that barrier. You can want a highly customized system without necessarily becoming an expert in every layer of the stack. If there’s some tweak or workflow that isn’t exposed through a settings menu, you can increasingly just describe what you want and have the system help you build it.
So I think the interesting shift is that software becomes less constrained by what the average team or individual programmer has the bandwidth to build and maintain. That could make both native apps and highly personalized computing environments much more viable again instead of the web-slop that we've become accustomed to over the past 20 years. I really see parallels between how the Mac empowered creatives in the 80s and agentic coding today.