I don't find the list of exceptions so bad. They're ones where you either pronounce the letters ("PC") or where it would be genuinely confusing "SAD").

I guess the question is, what is the value of styling "Aids" such? My assumption is that they would say that such acronyms have become words in English, people understand "Aids" or "Nato" as a "thing" and don't even think of it as an acronym (just like "scuba diving" or "laser" or "radar").

If it has basically become a word, it just slows reading down to write it in all caps.

...but I can see it's a debatable issue. This is probably one of those things where some words will become like "laser" and "radar," and some won't. BBC is trying to be on the forefront in guessing which words will be.