Yes, have a “VanTrue” brand from Amazon
Has front and rear cameras, embedded GPS data on screen which shows speed at all times in the video.
There’s a lot of reasons for having one, most having to do with showing objectively what happened during a collision. Otherwise it’s your word against theirs in situations where fault isn’t clear.
The only reason I can think of for not having one is you’re someone who drives like a jackass. In that case it would be recording you doing so.