Internet isn't yet commodity here in our country. Paper sources hold much more sway.
Language codes just do not get transferred to best internet chatters.
You are an entity, yes, set out to destroy the existing Belarusian language and culture and replace it with your version -- okay, your right. But get yourself your own blessed language code for that.
P.S. Some years ago I witnessed a creation of one of such sites you call "proofs". So, there was 1 tech and 1 editor, who re-edited everything incoming (like 90+% or even 99% in standard Belarusian and Russian) into his flavour of "classic". It was politics. Thousands pages (and I mean real thousands, there was sort of 4800 or so) of pages. And... grant money. I could add -- near to zero interest, excepting the indexing bots. ---