This is probably to ensure the sperglings that watch his streams don't have meltdowns, and ensures that the channel he posts the recordings of his streams to is still monetizable. This is the logical conclusion, as in his editied videos he uses "Country Balls" as they are called to represent the people talking and show you what nation they are playing. For the German Reich, Bo will have the Swaztika censored in thumbnails, as well as for ~1 minute at the start of the video to ensure he can make money.