Apologies for taking so long to respond to your question. It's been a long time since I made these changes so I'll try my best to explain it all 😄.
There is a good [thread over here][1] that gets into some more specifics but the issue with excluding the .xcodeproj/ in its entirety is that you are excluding files that shouldn't be excluded and may need to be shared across development team members. The additional rules I added address this problem of simply excluding the entire folder.
In order to address the additional rules I added in [patch-1][patch] I have included the follow tree output of an Xcode project; in particular, the .xcodeproj/ folder. I will use this to reference rules #2, #3 and #4 below.