https://www.in-ulm.de/~mascheck/various/shebang/#env https://www.in-ulm.de/~mascheck/various/shebang/#env mentions other OSes that have only /bin/env, although

https://www.in-ulm.de/~mascheck/various/shebang/#env https://www.in-ulm.de/~mascheck/various/shebang/#env mentions other OSes that have only /bin/env, although admittedly they are all quite old.