Side effects of changing the default shell in macOS to a Homebrew location

Some people prefer the latest Bash version for macOS (because /bin/bash is still a version in the 3.x range). This can be changed with this:

brew install bash
chsh -s /opt/homebrew/bin/bash

**However**, what are the implications and possible complications of using a path that is user writable and potentially vulnerable to corruption, such as - accidental deletion of the referenced login shell, - destruction of the /opt/homebrew/bin/bash symlink, which normally points to a specific version of bash, - malicious software that may exchange the symlink and replace it with a Bitcoin miner etc.