If you had read anything you'd know the primary goal of the new, more frequent, release schedule is to move to smaller and therefore less buggy releases.
I'm not saying there is anything there, but I never trust the search on GitHub under any circumstances. It routinely doesn't find things I am positive exist on my own code bases.
Idk about no crease but Samsung's appear to be the most noticeable from what I've actually seen. I think other manufacturers have improved on this over time but I haven't seen anything newer than my Pixel Fold in person.
IIRC display and chip manufacturing are basically treated like separate businesses from the phones as a product. And all the other companies foldables are better than Samsung's (imo at least) because they haven't innovated or improved in several generations.
The latter.