I think the author swapped problems #1 and #2. The first one (name clash between different packages) is triggered only if the binaries are called the same, that is after you fix the second one (binaries having uu- prefix).
Problem #5 is not well explained: if /usr/bin and /usr/sbin are conflated, how could cowsay not find its templates? Paths relative to the two directories are the same. For example, if cowsay is looking for its templates in ../share/cows, such relative path points to the same destination no matter if the binary is in bin or sbin.
Thanks for reading so closely and providing great feedback!
You are totally right on problems 1 and 2 being swapped.
For problem #5, you caught me taking too large a logical leap and making some assumptions there. Turns out the issue is just that cowsay special cases directories called `bin` (and thus treats directories called `sbin` differently)[0].
I just pushed an update to the post correcting both of these.
Problem #5 is not well explained: if /usr/bin and /usr/sbin are conflated, how could cowsay not find its templates? Paths relative to the two directories are the same. For example, if cowsay is looking for its templates in ../share/cows, such relative path points to the same destination no matter if the binary is in bin or sbin.