Bringing home a baby is an exciting and intense experience, especially if it's your first baby. First time parents are, understandably, a bit more on edge and cautious than more "experienced" parents. In fact, the obviously difference between taking care of your first newborn vs taking care of your second newborn is proof positive that if anything can aid you in parenthood, is experience. Lots, and lots, of experience.
I was a nervous wreck caring for my oldest son and, as a result, would definitely consider myself a helicopter parent (at the time, anyway). I read all the books, did all the research, joined all the Facebook mom groups. I made logs and charts, sensory bags, and facilitated explorations. We had cloud dough and play dough and sticky dough. If you could make it for babies, I made it. He painted with berries, he drew with charcoal, he had edible bath tub paint. I was off the rails and just a little-too-attentive and, well, I was a new mom.
Then my second baby came along and I just didn't have the same level of motivation. It was a wholly different experience with him. I'm not saying he's neglected, because he's definitely not. He's cared for and loved beyond measure, but he has a lot more autonomy than his brother did. He entertains himself, whereas his older brother was never given the opportunity to entertain himself.
I'm pretty confident this is not an isolated phenomenon. Ask any parent and they'll most likely agree (I hope), that caring for your first baby is significantly different than caring for your second. Hey, you live and learn, right?