Seriously, this script may destroy your machine and require a rebuild. It may have varied results on different machines in the same environment. Think twice before running this.

I don't think "machine" is defined as "installed packages". And reading the code of the script, the breaking part is the whole script, as 90 lines are literally just for the purpose of getting, changing and reapplying the path variable. It (or rather the system and user one) are also backed up to C:\PATH_backups_ChocolateyUninstall.txt.
So it's still a wonder for me how removing something from path, or adding for that matter, is so complicated. Linux just has /usr/bin and /usr/local/bin for custom scripts/programs globally, and .local/bin for user specific executables. If you really want custom paths for your special application then add a script in /etc/profile.d/. No need to permanently change a global variable that could easily break your system at any time.

TL;DR Windows is dumb for having global PATH variables without a way to expand them modularly, which would be much safer.