I am not sure how much a list of constraints on player character options has to do with "frustrated author railroad DM syndrome" -- could you please explain how you got there?
I think the issue is less the list existing and more what is on the list.
TV Tropes used to promote a trope of the Five Races where a setting would tend to have 5 standard type of races (The Stout, Cute, High Men, Fairy, and Mundane). Then there are the 4 classic class groups.
If your restrictions narrows things down under the "Five Races" and "Four Class Groups", it is too different from standard D&D and might cause issues with many players.
Then you get into customization options via other classes, races, feats, or whatever.