those scripts not always work
This feels like ragebait. I have multiple devices, use fish whenever that can be installed and zsh/bash when not, and have none of these issues.
EDIT:
or some methods to jump to most recent directory like z.
Manually downloading the same shell scripts on every machine is just doing what the package manager is supposed to do for you. I did this once to get some rust utils like eza to get them to work without sudo. It's terrible.