Something that strikes me as a bit odd is that most US electric buses seem to come from companies who just make electric buses. The electric buses here are made

Something that strikes me as a bit odd is that most US electric buses seem to come from companies who just make electric buses. The electric buses here are made by conventional bus companies who've been making buses for, in one case, 80 years an in another over a century. Do none of the traditional US bus companies make electric ones?