Comments by "eDoc2020" (@eDoc2020) on "Never Use Emojis In Your File Names" video.

@jonathanbuzzard1376 Old-school Macs let you use / in filenames long before users would've been concerned with SMB support. When switching to the Unix-based OSX they needed compatibility systems. When you enter a / in the GUI it is converted to a : for the Unix filename (and vice versa). I presume they used : as a path separator in old MacOS. I had no idea this was a thing but I was helping somebody with a file not opening. Apparently Word for Mac does not do all the necessary translations and simply can't open those files.
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Copy and paste, various IMEs, or just download a file with an emoji in the original name. Social media users often use emoji in titles, downloading such media will often copy it as (part of) the filename.
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@jonathanbuzzard1376 My experience with this was in 2018-2020 so it probably still has the same behavior. Not using ISO format was in this case ignorant. The user was just typing dates as they otherwise would and I'm sure sorting wasn't a concern. The real problem is that it lets you use a slash even though it breaks things. To a typical user there's nothing abnormal about using a slash.
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Emoji belong in passwords. I don't know why anyone would put them in filenames.
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