Yes, zsh is the now the default shell used by macOS Terminal. The switch has to do with GPLv3 licensing restrictions preventing Apple from using a newer version of bash.
It is not really necessary to install bash. There is already a copy on your system, HOWEVER, you need to be able to launch Terminal to run the command that switches from zsh to bash. BESIDES, I do not think it is zsh that is at fault. I think there is something else wrong with your macOS Terminal.
macOS Terminal should not be crashing.
The crash report says you have macOS Terminal 2.13, which is the same as is on my Ventura 13.4.1 (c) system.
The next thing to try is booting into Safe mode. Safe mode brings up a minimum macOS system, in some cases using more conservative drivers, and it does not load any 3rd party additions.
Boot macOS Safe Mode: Start up your Mac in safe mode - Apple Support
At this point, I would consider re-installing macOS Ventura OVER Top of the existing installation. As long as you do not erase your existing disk, the re-install will just replace the existing macOS operating system bit, including macOS Terminal, and will leave all your personal files alone.
How to reinstall macOS - Apple Support
Another approach is to try installing a different terminal emulator, such as iTerm2. This has 2 benefits. First, you would have a working terminal emulator and you could get on doing whatever you were planing to do. Second, assuming iTerm2 worked, then it would point to an issue with macOS Terminal, and not something they have in common, such as zsh (which I do not really think is at fault).
https://iterm2.com
Regardless of whether iTerm2 works on not, I strongly suspect you are going to need to try the macOS re-install. But iTerm2 might allow you to work in a terminal emulator doing your tasks, until you have time to do the re-install.
And if the re-install fails to correct the problem. The only idea I have left, is a Nuke & Pave. That is to say, backup your system, so all your personal files are safe. Maybe make 2 backups, using 2 different backup utilities, going to 2 different backup devices. This will make sure that a failure in software or hardware does not result in loosing any of your data.
Erase and reinstall macOS - Apple Support
During the initial setup after the re-install, when it asks if you want to transfer data from a backup or other system, point to one of your backups.
This is a measure of last resort. It should not be necessary, and if you can find anyway to avoid this, you should explore it.