From the about section (emphasis added):

>Subreply was created by Lucian Marin from the desire of a having a simple to use, English only, public forum that has nothing in common with ancient and untrustworthy social networks.

[...]

>Limitations

>480 characters per reply ASCII only because it works everywhere

I could see this being a xenophobic thing, but I could also see it being more about the limited character set (for minimalism). I'm not making a claim about the motivations, but either way your desire seems counter to his vision.