IDE-specific files aren't necessarily auto-generated. They might include project-specific configs (random examples that come to mind include linter configs, tab/space indent settings, C library include paths)

> imagine those git conflicts

Not an issue

> why they would want to commit IDE generated files

You added the word generated.

Many Windows-oriented projects a Visual Studio .sln file. This is great! You can open the sln, build, and run. It “just works”. Very nice. I wish more projects did this.

> what happens if people want to use different IDEs?

That’s fine. Nothing stopping it.

Jetbrains' .DotSettings file is a specific example. It contains things like project specific dictionaries for the IDE's spell checker.

I utterly fucking despise that Git allows ignored files in some cases. FUCKING DESPISE.

IMHO the .gitignore should be the source of truth.