I was completely unaware of this as well. Seems extremely strange that someone is getting triggered by the use of a word originally coined to refer to/insult robots in Sci fi, being used in the same context in real life - just because some degenerates in some internet niche are now using it in a somewhat actually-racist way. If that's how you live your life, you'll be triggered by literally everything.
Clearly there's been some strong parallelism in usages of clanker and nagger, just as there were in usages of ginger and its anagram by Tim Minchin in his song Prejudice.