My parents divorced when I was about six. My dad traveled for a living so wasn't around much before then, so in that sense it didn't seem a big change. As far as staying together - I guess it would have been nice if they could, but there were substance abuse and mental health issues and they kind of reached the end of the line.
Both tried to be good parents nonetheless, and my mother remarried and that was a good stable relationship.
As for effect - yes. Having a step dad, even a good stable one who largely supported me was stressful at times - not the same as a parent. There was a sense at time of being a bit of an outsider in someone else's home, dependent on someone who did not belong to you entirely. I was very hesitant to ask for things like money, even for school. I felt like I was asking a big favour. At my fathers home, on the other hand, because I was there less often and in some cases I had no room of my own, it never felt like I was at home there, I was a visitor.
So a real sense of displacement though as I child I couldn't really name that.
My brother struggled with it more, particularly when my half-brother was born some years later. He never remembered living with our father but was able to see that my step father felt himself to be a father in a way that he didn't with us. I was old enough to understand that was pretty natural, but he was not, and it affected his teen years a lot IMO. (Not that my step-father made an issue of this but you didn't have to be all that perceptive to see it.)
There was also friction between the extended families, and my my parents, even though they tried to hide it, that was a real stressor for me.