Unix has had a long running convention of separation between “operating system” and other files, so you can blow away something like /opt or /home without making your system unbeatable.
If you stick stuff under /usr/bin then you have to track the files especially if there are any conflicts.
Best to just add another path, I use ~/bin because it’s easy to get to and it’s a symlink from the git repo that holds my portable environment, just clone it and run a script and I’m home.
Fyi /usr/local/bin is for system wide applications, freebsd and it’s friends use it for non-core software installs.