That’s why you put things like #!/usr/bin/env bash. You can argue about which version of bash supporting which feature, but being afraid to have your own script

That’s why you put things like #!/usr/bin/env bash. You can argue about which version of bash supporting which feature, but being afraid to have your own scripts interpreted by POSIX sh is strange in the vast majority of situations. It’s like complaining that a C++ source would not be compiled by a strict C compiler. Or that Python 3 scripts should be valid Python 2 because you never know which version ‘python’ might be. Just use the right interpreter.