You can use command -v in any POSIX compliant shell. csh is not POSIX compliant. Your list of shells in inexhaustive to the point of being almost misleading. bash and zsh are "heavy-weight" shells, a lot of lightweight shells also support command.
If you're specifying your shebang as #!/bin/sh then you should not assume you have access to functions like type or binaries like which, but you can generally assume you have access to the command built-in.
Well the point is that it's a shell component, so it's not available from anything other than a shell which is undesirable.
I understand Bourne style (POSIX) shells have the vast majority of the market, but the point is breaking other environments. "command -v" is not available everywhere so it is not a viable replacement for /usr/bin/which.
If you're specifying your shebang as #!/bin/sh then you should not assume you have access to functions like type or binaries like which, but you can generally assume you have access to the command built-in.