I'm not against a new symbol at some point, but don't think it's a problem to reuse a fairly obscure one
The Thai economy positively dwarf's that of bitcoin - so what sort of crazy definition of 'obscure' are you using?
There are more than a handful of Thai people living in my city.. I meet some of them now and then. (latest one just last week)
It would feel completely ridiculous to attempt to introduce them to this newfangled currency called bitcoin, which abuses the Baht symbol.
They'd rightly think it was a pathetic joke. Any selling point about it being potentially useful to transfer value to friends and family back home would be lost.