Right, I get that it’s not grammatically correct in that context, but the word itself is valid. I had always thought “learnt” was akin to “ain’t”, but that’s not the case. Both “learned” and “learnt” are correct, but the latter is less commonly used in the US.
The annoying thing is: if everyone did this, phantom traffic jams wouldn’t be a thing, and even real road obstructions would have significantly less impact and we would all get where we want to go faster, collectively. But we won’t, because I got mine.