I mean, it's less of an issue on Linux for both design and user profile reasons, but imagine a world where somebody can send all the normie Windows users a file called Chromesetup.exe to sit alongside ChromeSetup.exe. Your grandma would never stop calling you to ask why her computer stopped working, ever.
For example I might store blobs of data processed by my database in files that have the Base64 ID of the blob as the filename. If the filesystem was case insensitive, I'd be getting collisions.
Users probably don't make such files, no. But 99% of files on a computer weren't created by the user, but are part of some software, where it may matter.
And often software originally written for Linux or macOS and then ported to Windows ends up having problems due to this.
For files of casual users it might be of benefit. They don't care about capitalization. For system files, I find it pretty weird to name them with random capitalization, and it's actually pretty annoying. Only lower- (or upper-)case would be ok tho.
Well, camel case does help readability on file names. But I guess that's the point of case insensitive names, it doesn't matter. However you want to call them will work.