You may like my project https://charleswiltgen.github.io/Axiom/ (FOSS). I was in the same place a year ago, and initially created Axiom as a private skills suite before deciding that it was too helpful not to share.
And that's really sad, because earlier Mac OS X (and even OPENSTEP to a degree) was an Eldorado for boutique developers, not least due to frameworks like Cocoa and Objective-C (despite all the hate it seems to get).
If you knew C, it was not hard to grasp Objective-C (at least it was much easier than say C++ and MFC on the Windows side of things).
My first Apple purchase was an iPad I got for my aunt, and I loved how streamlined yet powerful it was so I installed a VM on Windows to dabble in iOS development, and fell in love with the sheer consistency of macOS, iOS and their APIs.
This was during the era when Microsoft was still figuring out whether to keep the Start Menu and replace the whole Windows UX with a tablet UI, so it was an easy jump.
Almost never looked back, and whenever I do I'm glad I jumped.
Then came Swift and I loved it, but then it took literal years to catch up with everything you could do in Objective-C with the Apple APIs. SwiftUI is having the same problem but for much longer :(