Ok, if you really prefer a dull, pedantic programmer's mansplaination, I will provide an answer in the style of a fellow software engineer who goes into such detail that run well past time in meetings :
(

No offence meant if he is reading this thread though).
Emojis are unicode characters which execute graphical code when displayed, this breaks expected historical norms from filename display code dating back from the first graphical user interfaces of the 70s.
As such behaviour is not expected to happen with standard IO files, this is counted as an exploitation bug and not a feature to be reliably act in a predictable fashion.
Therefore, filenames with emoji in them are probably not going to have full support for error free file transfer until all operating systems support the emoji characters within the filename string.
This would probably become a supported feature no earlier than 2020 for conventional computers due to timeframe before macbook pro touchbar has an equivalent feature on sufficient PCs to be supported by Windows and Linux distros.
It is almost certain that it won't ship with High Sierra, however it may become possible once APFS is deployed as a part of a point upgrade to High Sierra.
Although in my opinion, this would be more likely to take more work than it would seem, as once this is implemented, then everytime emojis are added to the standard, a new set of emoji must be added as a possible filesystem character and backported to the still supported versions of MacOS, which leaves older versions of MacOS vulnerable to crashing if they receive a filename with emoji or new emoji unsupported in the obsolete version of MacOS.
To be clear, this would result in a minor amount of havoc for people with older macs who may end up not being able to run specific files at all simply because the filename is incompatible, and would break a convention since HFS in 1986.
TLDR; yes it is possible for future versions of operating systems to support emoji filenames, they do not now support it for reasons listed above, and if they did support emoji in the filesystem then there would be major problems with obsolete versions of MacOS being vulnerable to crashing just on individual files.
In other words, it would be a cheap way to crash an older computer without any effort.