A while ago, I installed Racket from the website (https://download.racket-lang.org/). I did the non-Unix distribution, so it did not come with the racket-uninstall script. I later decided to install Racket from apt so that I could receive updates without having to download them manually. This led to a conflict where both racket installations were active.
Racket from the shell script is installed to /usr/racket but there are also symlinks installed, so you need to do a bit more work to remove the installation. The following command can be used to find these extra symlink files to complete the removal:
$ find / -type l -exec readlink -nf {} ';' -exec echo " -> {}" ';' 2>/dev/null | grep /usr/racket
This uses find to find symlinks (-type l) and readlink to show their installed location. I assume this is all that is needed to clean things up.