Two words get used separately for a while. Then they are combined with a hyphen. Finally, they merge into one, new word.
There is no worldwide consensus about the day when A changes to B and B changes to C. It happens gradually. That’s the beauty of an evolving language.
But it does annoy me when people get the ‘hyphen’ in the wrong place. For example, when the ads talk about ‘laser-vision correction’. Not ‘laser vision-correction’ as it should be.
I don’t know anyone with laser-vision that needs it corrected. I do know people who would like vision-correction, with lasers.
I’m not suggesting that those particular words are, or ever will be, hyphenated. But I do wish voiceover artists would read scripts with meaning in mind.