The sh-bang notation was introduced in one of the early BSD releases (I think it was either 2.8BSD or maybe one of the 4.x series), some 15 or so years ago. At that time, the text after the sh-bang was limited to about 32 characters, and a single argument, and the path had to point at a "real" executable, all to keep this feature simple in the kernel.

I'm not aware of any current release of a unix-like thing that has taken the trouble to change that behavior.

You can use PAR to compile your Perl-script into a real executable, which can then be used on a sh-bang line. However, unless you're using libperl.so, you'll then have a completely separate Perl interpreter running for every instance of your application as well, meaning that you lose the benefit of the normally-common read-only pages of all existing Perl scripts. This has performance implications, although it won't affect the possibility of running the script.