its considered lazy copy paste coding
As someone who writes code for a living and has done some blockchain development.
That's irrelevant if the code works. A lot of the time devs are under extreme pressure to get a functional projects/features out . There's not much time to rename packages and modify forked code . That can be done later when the project matures.
Nothing is made from scratch anymore, most code is built on something else. Pancakeswap is fairly new so nothing there even remotely surprises me.
"Duck taped code" Is more common than you think. You'd be surprised how much of the shyt we use everyday is built very similar