Nothing a lie about it. It wasn’t used “sparingly” just not used by people who didn’t know better. Nobody is trying to appease China, it’s just intelligent use of terminology. If you’re writing a paper about the pre-colonial history of China and use BC and AD you sound like an idiot.
No. It’s NEVER been an issue. It’s used in the sciences all the time, for CENTURIES. The only thing that happens is that every few years some idiot “Christian” who wants to gin up fear to make money writes an article about how “they’re writing Christ out”. The “Christian” writing these articles is a liar, and the people who get freaked out about it are fools. I’m an atheist and I use the terms as they are MEANT.
There really is NOTHING in this for anyone who isn’t an idiot to complain about. Nobody is forcing anyone to use it. It’s commonly used where it makes sense, and often not used where it makes more sense to tie things to Christ’s birth. None of this has significantly change for over 200 years. If you’re upset about it you’re a fool being led by a liar.