I'm working on a "Unity for everything else". If you build an IoT product, most anything consumer facing, tools for small business, etc, your customers will expect a multi-platform experience. They want an app on iOS and Android as well as a responsive website. This is currently a pain in the ass to build. You either end up with a very carefully made architecture to share code or build everything a bunch of times or some combination. Huge budget problem. I know, I've had to do it...

Currently looking for people who would want to collaborate on some of the open source pieces that are needed.

Short term I think the right place to start is to build an open source toolkit leveraging NextJS + React Native to create a single project for all platforms.

Long term imagine an IDE (VS Code Extension), hosting, backend ecosystem, marketplace for themes and plugins, a simple opinionated project structure for building things that run on web, iOS, and Android to start. Eventually probably Desktop too. Based all on open source tools to avoid vendor lock-in.