You mentioned translator, so I’m going to assume English is not your native language.

Retarded actually means slow or slowed down, not specifically applying to people. For example, in a cumbustion engine you might have to retard the timing to get the spark and piston to sync correctly for firing.

Historically, it has also been applied to people with mental or learning disabilities which then became a common insult used to imply someone was stupid. Once it became an insult, it was considered rude in it’s original context even though in many ways it is an apt description. As such, many auto mods will filter out the word regardless of context.

You got it admit, it is a good suggestion. It just wasn’t the right one. But it is trained well enough to correlate left and right together. Since those are very commonly associated together it is certainly a logical choice.