I prefer to solve the problem in the right place. Raw concatenation of bytes without encoding-awareness introduces the possibility that the bytes will combine

I prefer to solve the problem in the right place. Raw concatenation of bytes without encoding-awareness introduces the possibility that the bytes will combine in unexpected ways. The presence of something as obvious as a BOM makes it harder to make this mistake, at least during the transition phase to "UTF-8 everywhere". What you really want in this situation is something that forces you to see the potential bug and introduce the correct translation and/or text-concatenation tools to fix it. And yes, at some point in the future enough tools will be truly aware of UTF-8 that the BOM will not have a reason to exist. But right now it has some value.