I recently noticed this, but a lot of youtubers seem to sound almost exactly the same, like there was a character creation screen with a choice of different voices to choose from. While this is most prevalent with American youtubers (both male and female) I notice a lot of British youtubers, and honestly a lot of youtubers who are the same gender with the same accent seem to sound the same as well.

This is kinda similar to the NPR host voice, or the news anchor voice where it seems like every NPR host of the same gender sounds the same and a lot of news anchors also sound the same.

Is this something they pick up or learn, something they intentionally edit for? (Is it just that people sound the same in general?) Similarly how do NPR hosts and news anchors end up with the stereotypical voice? I'm assuming they weren't born speaking like an NPR host or a news anchor