Zsh detects insecure completion-dependent directories

This is an issue with ZSH, your shell, not Hyper, your terminal. I actually had the same issue earlier today. There are some solutions in this issue on Github, and I will quote some of them here but I recommend you follow the link and read the comments there.

The first solution is to change the ownership of the problematic directories.

I will not recommend this without knowing more about your environment, but for most people this will fix the issue:

chmod 755 /usr/local/share/zsh
chmod 755 /usr/local/share/zsh/site-functions

The second solution is to set ZSH_DISABLE_COMPFIX=true (or "true" in quotes) in your .zshrc file, to tell ZSH to not check for insecure directories.

The third solution, and the solution that fixed the issue for me, is to initialise compinit with the -u flag. This will use all the directories found by compaudit without checking them for security issues. To do this, you will have to change your .zshrc file or wherever you are configuring autocomplete.

On my mac, what helped was running brew doctor

The program told me the exact commands to run!