Zsh Terminal [Process Completed] Error, out of memory

Just to add, for the benefit of the OP: since you can't run zsh, there are two ways you can rename the ~/.zsh_profile

a) temporarily change your shell to something else, like bash

(better yet, go to preferences->profiles, duplicate your basic profile, and in that duplicate select bash as the shel;

then you can do Shell->New Window and choose that profile to open a separate window running bash instead of zsh)

b) use the Finder (probably easier) - in the Finder press Command-Shift-H to open your home folder, then press

Command-Shift-. to show invisible files.

I have never seen Zsh kick out an error from ~/.zprofile about an out-of-memory error because I only use ~/.zshrc and do not run anything from that dot file that would cause a gobbling of memory.

In the Terminal Preferences Profiles > Window tab, I have Scrollback set to Limit number of rows to 1,500 and do not have that set to Limit to available memory.

When the shell process is killed, you get the [Process completed] notification. This too can be controlled for when you press ctrl-D to close the Window, but not quit the Terminal:

Try using the ~/.zshrc file with your PATH and PS1 prompt set. Just those two items. Rename your ~/.zsh_profile to zsh_profile.bak. Quit Terminal. Reboot. Launch Terminal again. If you do not get the out-of-memory error, then there was something in your ~/.zsh_profile that was borking Zsh.

If you have done the first paragraph and you still get a Zsh out of memory error, then that leaves your Terminal Preferences settings as a suspect.

Are you using the default Zsh version that was installed by macOS, or Zsh v5.9 installed via a package manager, or compiled by you from sources?