Git for games: current problems and solutions - Git Merge 2019

I've seen some game studios prefer the structure with owner folders, so they keep their files in safe place which nobody intends to merge back. In this case people just switch styles in configuration which also encourages more art options.
If somebody managed to tackle foreign files and commit them back, they should be filtered via custom Git hook which simply UNSTAGES these directories and passes one correlated to your commit email. That would be yummy!