Earlier quoted context omitted.
The Window Manager - nothing stopping you from using XWindows. The Finder - it's just a file manager, what's stopping you from using any other file manager? Cocoa - is just a Framework for building Mac apps. Nothing stopping you from using another Framework Xcode - just an IDE on top of open source build tools. IMessage - just a messaging program. Nothing stopping you from using another messaging program. FaceTime -…
Pfffft. Yeah there's "nothing stopping you" except for everything. You can't get rid of the window manager, the Finder or the Dock. Heck, you can't even stop Finder from running in any supported way and even if you manage to, you can't replace Finder in every program to open or save files. You can't replace the Dock because Apple won't let you modify a private API for describing available screen space. Every Dock rep…
https://www.howtogeek.com/259378/how-to-quit-the-finder-in-o...
Run x11 on the Mac.
I found the link from an Apple support page.
https://support.apple.com/en-us/HT201341
The Finder isn't used to "save files".
But alternate file managers...
https://lifehacker.com/5824343/the-best-alternative-file-bro...