The problem is really that space is an argument separator, so to safely handle filenames with spaces you need to handle them special, either by escaping them, quoting the entire thing. This means that the filename with spaces can’t be just copy pasted wherever you want, you have handle them special. It adds complications that are resolved by just using a separator that isnt used for other things, like underscore, or dash. Dot I also don’t like as much as it’s used as a separator for extensions, but that’s a far easier problem to handle by just ignoring all but the last dot, leaving only one really bad edge case (a file that does not have an extension, that uses dot separator in its filename having the filesystem imply a wrong extension.
That’s a problem with the shell though, not the filesystem. It doesn’t matter which files filesystem you’re using; most interactive shells use spaces as token separators and therefore spaces in filenames need to be enclosed in quotes or escaped.
The problem is really that space is an argument separator, so to safely handle filenames with spaces you need to handle them special, either by escaping them, quoting the entire thing. This means that the filename with spaces can’t be just copy pasted wherever you want, you have handle them special. It adds complications that are resolved by just using a separator that isnt used for other things, like underscore, or dash. Dot I also don’t like as much as it’s used as a separator for extensions, but that’s a far easier problem to handle by just ignoring all but the last dot, leaving only one really bad edge case (a file that does not have an extension, that uses dot separator in its filename having the filesystem imply a wrong extension.
That’s a problem with the shell though, not the filesystem. It doesn’t matter which files filesystem you’re using; most interactive shells use spaces as token separators and therefore spaces in filenames need to be enclosed in quotes or escaped.